Table of Contents

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A new variety of Haworthia Limifolia from Natal (1962)

Reprinted from “The Journal of South African Botany”, vol. XXVIII, part III, July, 1962

A NEW VARIETY OF HAWORTHIA LIMIFOLIA FROM NATAL

M.B.Bayer, College of Agriculture, Cedara.

The typical form of Haworthia limifolia is from somewhere west of Delagoa Bay and was described by Marloth (1908).  Prof. R. H. Compton has kindly sent me specimens from the Umbuluzi River Valley north of Stegi and also a form from near Gollel on the southern border of Swaziland.  Herbarium records show that forms also occur near Barberton;  the confluence of the Pongola and Pivaans River 20 miles east of Paulpietersburg; Ndumu, Zululand;  Kosi Bay, and the Ubombo Mountains in Zululand.  A photograph of a plant collected by Mr. E. R. Harrison 6 miles west of Somkele on the slopes of the Nkonyana Mountains, matches plants collected by me at Ngceba, north of the Black Umfolozi River, between the Umfolozi and Hluhluwe Game Reserves.  This form is also reported to occur on the nTsuzi and Ulumbi hills which flank the Umfolozi Reserve on the north and south.  Two plants have been collected from this area by Mr. H. Dent.  Mr. A. F. Bruyns-Haylett also records it from the Mozaan River Valley between Swaziland and the Pongola River (fig.2.)

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Haworthia as a problem genus (1970)

Printed in CACTUS AND SUCCULENT SOCIETY OF AMERICA 42:251-4 (1970)

M.B Bayer, National Botanic Gardens of South Africa, Karoo Garden, Worcester.

Although many enthusiasts have recognized the need for a better understanding of haworthia as they grow in the field, South Africa has been very slow in providing the necessary interest.  Mr. G.G. Smith did a vast amount of work only to withdraw from the field before this work could reach fruition.  As a result, even his contribution has done very little towards solving the fundamental difficulties in the group.  Practically all the errors which can contribute to unsatisfactory classification have been made.  Perhaps the most unfortunate, and the most forgiveable, has been the total failure to recognize the importance of locality and variability.  In other words haworthia have never been studied on a population basis.  This has led to unnatural sections in which only superficial morphological characters have been used, and too many superfluous species and varieties which have no basis as far as the distribution of the plants is concerned.   Floral structure has several times been suggested as a possible solution to the problem of identification, but has never led to any further conclusion.  Why, of course, is very obvious.  To try and establish order from false foundations will never succeed.  The basic premise that the species described are true representatives of morphologically and geographically distinct species has never been questioned for the haworthia.  New species and varieties were freely described by Smith, von Poellnitz and Uitewaal (and Resendé) although the real identities of Haworth’, Salm Dyck’ and Baker’s species were in many cases unknown.

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Variation in Haworthia with particular reference to HAWORTHIA GLAUCA, Baker. (1970)

Written for, and then printed and distributed by Haworthia Study Group, New South Wales – October 1970.

M. B. Bayer, Karoo Garden, Worcester, South Africa.

Much of the confusion in the taxonomy of the genus Haworthia could have been avoided if more attention had been paid to localities and inherent variability of the species.  The tendency has been to base species on single specimens and to regard the species as variable concepts subject to personal opinions.   According to Stebbins in his book “Variation and Evolution in Plants”, a species comprises a system of populations separated from each other by complete or sharp discontinuities in their variation patterns, and this must have a genetic basis.  Therefore there must be isolating mechanisms to prevent transfer of genes. In Haworthia, most (not all) of the species are found in rock formations and stable situations at moderate altitudes, and hence the populations are well spaced.  Haworthias are also insect pollinated, mostly by solitary bees, and as stated by Clausen in “The Evolution of Plant Species”, it is logical that spatial separation of the plant populations coupled with flight limitations of the pollen vectors, will with time have led to differentiation of highly localised populations.  A further problem in Haworthia is that the species do in fact exist at different stages of differentiation.  Thus one may be forced for practical reasons to regard a widely ranging series of varying populations as a single species, simply because the degree of  inter-gradation and variability precludes any other alternative.  If there is an alternative, it is to recognise varieties in the sense that this concept has been used in the past, i.e., to apply to individual variants and forms.

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Changes in the genus Haworthia Duval (1971)

Printed in Cactus and Succulent Journal (US), 43:157 (1971).

M.B.Bayer, National Botanic Gardens of South Africa, Karoo Garden, Worcester.

The genus Haworthia is sub-divided into twenty sections principally on leaf and growth habit.  The composition of the sections thus often bears little relation to the actual and natural affinities of the constituent species.  Sub-division of the genus on the basis of floral characters has been suggested by Uitewaal (1947) and reference should also be made to Berger (1908).  In Das Pflanzenreich, under the Section Margaritiferae, Berger particularly comments (citing N.E. Brown) on the problem of garden hybrids, and it is unfortunately true that many species are still recognized which have no real basis in field populations.  These inevitably obstruct attempts at presenting natural relationships, and hence also a desired aim of plant classification.  The inadequacies of leaf morphology as a basis for subdivision is particularly evident in a study of the species H. reticulata Haw., H. herbacea (Mill.) Stearn and H. schuldtiana var. maculata vPoelln..  These species are presently placed in the sections Muticae, Arachnoideae, and Retusae respectively, when in fact distribution, inherent variability, field hybridization and floral morphology demonstrate their unquestionable affinity.

The section Margaritiferae is particularly afflicted with dubious species and there is some doubt that the species H. icosiphylla Baker, H. tisleyii Baker, H. rugosa (S.D.) Baker, H. .cuspidata (S.D.) Baker, H. subattenuata (S.D.) Baker and H. subfasciata (S.D.) Baker can be referred to field populations and thus validated.  On the basis of floral morphology, the species H. attentuata Haw., H. browniana vPoelln, H. fasciata Willd., H. glabrata Baker, H. longiana vPoelln. and H. radula Haw. (if these are actually discrete species), together with H. smitii vPoelln.and H. tuberculata vPoelln. whose affinities are less obvious, can be transferred to the section Coarctatae.  Examination of preserved material in the Bolus and Compton Herbaria (Cape Town), collecting records of Smith, Otzen, Long and Payne, and direct field observation indicate that only four species need to be considered under the Margaritiferae.  The following account is given in explanation of this statement.

The described varieties and related species of H. margaritifera (L.) Haw, are particularly confused and it is fortunate that field populations do not make it necessary to fully clarify the involved synonymy of this species.  Commelin (1701) recognized two species, Aloe africana folio in summitate triangulari margaritifera flore subviridi (t.10) and Aloe africana margaritifera minor (t.1l).  In 1715 he added two more species, one merely with fewer tubercles and probably synonymous with both his t10 and t.11, and Aloe africana margaritifera minima (n.43) which was described as having smaller leaves and tubercles than the variety minor.  Boerhaave (1720) cited four related species but referred only to two of Commelin’s earlier species.   Bradley (1725) described and illustrated a plant which he vaguely referred to Boerhaave.  This is unfortunate because although Bradley’s illustration (t.21) is clearly intended to be the same as Commelin’s minima, it became a source of confusion in later works.  Dillenius (1732) elaborated on Commelin’s species and provided illustrations for separation of the elements minor (f.17) and minima (f.18).
Linnaeus recognized three elements which were based on Commelin’s t.10, t.11 (Dillenius’ f.17) and n.43 (Dill. f.18), Aiton (1789), in retaining three elements, cited only Bradley’s t.21 under his Aloe niargaritif era var. major and yet under the variety minima also refers to Bradley’s species!  DeCandolle (1799) illustrated a plant (t.57) as Aloe margaritifera and this was said by Ker-Gawler (1811) to really have been the variety minor.  DeCandolle had used the epithet media instead of minor, and as Ker-Gawler (1805) had repeated the error it is not surprising that Aiton (1811) added Decandolle’s t.57 and KerGawler’s media to the synonymy of his Aloe margaritifera var, minor.   It is perhaps Aiton’s earlier treatment of Bradley’s t.21 which prompted Haworth (1805) to recognize four elements, namely Aloe maxima (type Commelin t10), Al. minor (type Comm. t.11 and Dill. f.17), Al. minima (type Comm n.43 and Dill. f.18) and Al. major (type Bradley t.21).
Willdenow (1811) appears to have been confused as he described Apicra margaritifera var. major (type Comm. t.10 and Bradley t.21) and var. minor (type Dill. f.18).  He also described Ap. granata (type DeCandolle t.57) and Ap. margaritifera var. maxima (no syn.).  This latter species may have been intended to be Haworth’s Al. maxima.  Salm-Dyck (1817), however, altered Haworth’s Haworthia maxima to Aloe semimargaritifera with three varieties major, minor and minima, and described Al. papillosa based on Willdenow’s Ap. margaritifera var. maxima.  It seems fairly certain therefore that Al. papillosa S.D. and H. maxima Haw. were synonymous. Saim-Dyck retained Al. margaritifera and also its varieties major, minor and minima.

Haworth (1819) now totally revised his species by accepting Salm-Dyck’s Al. semimargaritifera and adding a fourth variety multiperlata.   He altered his H. margaritif era var. major to the species H. margaritifera, retained H. minor, described H. erecta (type DeCandolle t.57) and H. brevis (type Ker-Gawler t.1360), and altered his H. minima to H. granata.  He also discarded his H. maxima in favor of H. papillosa.  The species H. semiglabrata was also described.

Some rationalization has taken place with time and the following species and varieties arising from the above are presently recognized : –
H. papillosa (S.D.) Haw.
Hf. margaritifera var. margaritifera (L.) Haw. var, corallina Baker
var. maxima Haw.
var. minima (Aiton) Uitew.
var. minor (Aiton) Uitew.
var. subalbicans (S.D.) Berger

In addition there are several subvarieties and also the related species H. semiglabrata Flaw., H. poellnitziana Uitew., H. uitewaaliana v Poelln. and H. mutabilis v Poelln.

Field observation clearly demonstrates that all these taxa are misconceived and that historically, confusion revolves around two principle elements.  These are firstly the species typified by both Commelin’s t.1O and t.11, found in the Robertson Karoo and western area (Montagu) of the Little Karoo. This is H. margaritifera  (now H. pumila).  Secondly there is the species found in the Coastal Renosterbos and Machia veld-types and typified by Commelin’s n.43 (Dill. f.18).  This is H. margaritifera var. minima and upheld by the writer as a distinct species, H. minima Haw.  This species is not to be confused with Baker’s illegitimate H. minima for which the name H. tenera v Poelln. was upheld by Uitewaal.

H. poellnitziana was investigated at its type locality at Drew, and a related population was also examined in the same ecosystem some three miles to the north-west.  The type locality is a very restricted area and Mr. G.J. Payne communicated the information that H. marginata var. virescens (Haw.) Uitew. had previously been determined from this same site.  Some specimens collected at this locality by the writer showed evidence of smoothness typical of H. marginata (Lam.) Steam and the presence of hybrids of this species with H. niargaritifera nearby at Ashton indicate that H. poellnitziana may be of hybrid origin.  The population to the northwest can either be considered to be a larger form of H. minima more like those found in the inland areas from Riversdale to Swellendam, or to be an ecotype of H. margaritifera adapted to the sandy soils of the Coastal Renosterbos veld-type.  The problem is illustrated in the accompanying photographs.  For the present, H. poellnitziana can be regarded as a variety of H. miargaritifera.  Plants and seed from the type locality are in cultivation at the Karoo Garden and these will permit a final diagnosis at a later date.

H. papillosa can be dismissed as a variant of H. margaritifera with little further ado.  Apart from having its origin in Commelin’s t.1O, field observations show that any of the attributes by which this species can be considered discrete, are fallacious.  Under good conditions H. margaritifera may grow enormous and often develop an elongated leafy stem.  The density of tubercles is in any case variable and it is not uncommon to find the leaf faces smooth either.  In some specimens the leaves are arranged in conspicuous spiral fashion also.
The discovery of H. mutabilis vPoelln. is attributed to G.J. Payne who recorded it from the farm Mierkraal, south-west of Bredasdorp (also the type locality of H. mundula Smith).  Mr. Payne informed the writer that the species was based on an atypical specimen of H. minima, which was the only relevant species found by the writer in that area.  Thus H. mutabilis cannot be upheld and is reduced to synonymy under H. minima.

H. marginata hybridizes commonly with both H. margaritifera (N. and S.E. of Ashton) and with H. minima (S. of Heidelberg).  These hybrids are undoubtedly the origin of Zantner’s curious paper which appeared in Beitrage zur Sukkulentekunden (1942), the one real merit of which was the statement that H. marginata and H. margaritifera were closely associated species and needed to be considered in the same context.  H. semiglabrata certainly offers no problems and specimens satisfying the description for this species are common in the hybrid swarm H. margaritiferaX marginata near Ashton.  Similarly H. uitewaaliana must be dismissed as another form within a similar hybrid association, if not described from a luxuriantly growing young specimen of H. marginata.

There is some doubt as to the origin and validity of H. subjasciata S.D.  The variety kingiana vPoelln, is quite distinctive and occurs in a different ecological area, notably the Karoid Valley Bushveld of the lower Great Brak River.  Thus H. kingiana is upheld by the writer as a distinct species, the species subfasciata being discarded as dubious.

The four species are thus H. margaritifera, H. minima, H. marginata, and H. kingiana.  All these species have a characteristic heavy branched peduncle to which Berger and N.E. Brown (1878) refer, and for which Uitewaal proposed recognition as a subdivision Robustipedunculatae of his group Hexangulares.  Also characteristic of these species is the abruptly rounded attachment of the perigon onto the pedicel.  This, coupled with the relatively narrowly opening perianth lobes and regular arrangement of the outer lobes, separates the four species from all other Haworthia.  The large rounded seed capsules and characteristic configuration of the empty capsules are also distinctive.  These all suggest a distinct component of the genus at sub-generic level together with the groups Triangulares and Hexangulares proposed by Uitewaal.  The nature and degree of difference between the three subgenera so formed appears to warrant re-evaluation of at least the genera Astroloba, Chortolirion and Haworthia.

The writers concept of subdivision of the genus Haworthia is implemented as follows:-

Haworthia Duval subgenus Haworthia
Type: H. arachnoidea (L.) Duval
Plantae acaules, folia carnosus, pedunculus gracilis simplex, perianthium  ad basim triangularis vel rotundatus triangularis, tubus subabruptus junctus versus pedicellus, stylus brevis flexus, stigma sursum capitatus, capsula elongatus cylindricus.c (The name Triangulares proposed by Uitewaal for this group cannot be accepted on account of Article 22 of the International Code of Botanical Nomenclature).

Haworthia Duval subgenus Hexangulares Uitewaal
Type: H. coarctata Haw.
Plantae acaules vel caulescentes, folia rigidus firmus elongatus vel plantae caulescentes folia abbreviatus incrassatus, pedunculus gracilis plerumque simplex, perianthium ad basirn hexangularis vel rotundatus hexangularis, tubus decrescens versus pedicellus, stylus elongatus erectus, stigma prorsus subcapitatus, capsula elongatus cylindricus.

Haworthia Duval subgenus Robustipedunculares Uitewaal
Type: H. margaritif era (L.) Haw.
Plantae acaules, folia rigidus incrassatus, pedunculus robustus ramosissimus, perianthium hexangularis, vel rotundatus hexangularis, tubus abruptus junctus versus pedicellus, stylus elongatus erectus, stigma prorsus subcapitatus, capsula grandis rotundatus.

The following key divides the genus into the three subgenera : –
1. a – Perianth at base triangular or rounded triangular…………………………… Subgenus Haworthia
b – Perianth at base hexangular or rounded hexangular…………………………………….. 2
2. a – Perianth gradually narrowing to junction with pedicel………………. . . . .Subgenus Hexangulares Uitewaal.
b – Perianth abruptly joined to pedicel Subgenus ……………………………Subgenus Robustipedunculares Uitewaal.

The sections as recognized at present are allocated to the subgenera almost as indicated by Brown (1957), with the exception of the section Albicantes which now falls under the subgenus Robustipeduinculares.  The Robustipedunculares therefore includes the species H. margaritifera, H. minima, H. kingiana and H. marginata.  The sections Albicantes and Margaritiferae can be retained in this subgenus with the exclusion of the dubious and invalid species already noted, and the exclusion of those species transferred to the Coarctatae.  The further correct and natural breakdown of the subgenera will require an intensive study of both floral and leaf morphology.  As already indicated, the present sections are not natural, and natural groups cannot be constructed on leaf structure and arrangement alone.  For example H. marginata is separated from H. margartifera on the basis of leaf armature (glabrous and tubercled respectively) yet flower structure conclusively demonstrates their proper affinity.  It is conceivable that the glabrous H. starkiana vPoelln. and tubercled H. tuberculata vPoelln, may prove similarly related.  Rationalization of the differences between the four species constituting the subgenus Robustipedunculares is relatively easy.  H. marginata is separated immediately by its glabrous leaf surface.  The inflorescence is similar to that of H. marganitifera except that the perianth lobes are white suffused with pink.  H. marginata has been recorded from north of Bredasdorp, west of Napier, south of Swellendam, Heidelberg, Riversdale and also north and southeast of Ashton.  It thus occurs principally in the Coastal Renosterbos veld-type except at Ash ton where it is found in Karoid Broken veld.

H. kingiana is separated by its more brilliant green color, fewer tubercies, and tubercles which are rounded, smooth and hardly projecting above the leaf surface.  Ecologically this species is separated by its distribution.  It is confined to the Karoid Valley Bushveld east of Mossel Bay, although this veld type is also found in part of the Gouritz River Valley to the west.

H. minima and H. margaritifera pose slight problems.  There must be doubt in view of what has been written concerning H. poellnitziana, that these two species are separable.  H. minima is characteristically smaller in the coastal areas, but inland may reach a height of 10 cm. and 8 cm. diameter. Although H.   margaritifera may also be small under adverse conditions, it often reaches a height of 30 cm. and 20 cm. diameter. It is also more coarsely tubercled.  The leaf ground-color in H. minima is grey-green and the tubercles distinctly white, whereas in H. margaritifera the ground color is dark-green varying through to deep brick-red under adverse conditions.  H. minima frequently forms dense compact clusters.  H. margaritifera seldom proliferates and when it does the plants are often characterized by the visible, elongated stems with dried and missing basal leaves.  The color of the outer perianth lobes is usually a distinctive yellowish-brown in H. margaritifera compared to H. minima where they are pinkish-white.  Finally the perigon in the former species may be up to 4.5 mm. in diameter and seldom more than 2 mm. in the case of H. minima.

Ecologically H. minima ocurs in the Coastal Renosterbos and Coastal Macchia veld-types which are associated with sandy soils.  H. margaritifera occurs in the heavier clay soils derived from Karoid shale formations, and in the associated Karoid Broken veld of the Robertson, Bonnievale, Worcester and Montagu areas.  Morphological differences are maintained under cultivation in same soil mixtures and growing conditions.  With those differences in mind, the correct decision appears to be separation at species level.  There is no evidence to support the multiplicity of varieties and sub-varieties presently recognized, and even the variety poellnitziana would be more correctly treated as anomalous.

The sub-genus Robustipedunculares is expected to key out reliably in the following manner: –
1. a – Leaf surface smooth……………………………………….. H. marginata (Lam.) Stearn.
b – Leaf surface tubercled ……………………………………… 2

2. a – Tubercles smooth rounded, hardly raised above leaf surface… H. kingiana vPoelln.
b – Tubercles rough, distinctly raised above leaf surface………… 3

3. a – Leaf color gray-green, plants small (to 10 cm. high) outer perianth lobes pinkish-white… H. minima Haw.
b – Leaf color dark-green, plants large (to 30 cm. high), outer perianth lobes yellowish-brown…

….. H. margaritifera (L.) Haw.
Leaf color is not a reliable criterion for separation of these species as obviously under artificial conditions the usefulness of this chararater may diminish.

LITERATURE CITED
Uitewaal, A. J. 1947. A first attempt to subdivide the Genus Haworthia based on floral characters. Desert Plant Life 19; 133-138.

ACKNOWLEDGEMENT
The writer wishes to acknowledge the interest, encouragement and assistance received from Mr. F. J. Stayner, Curator of the Karoo Garden, Worcester. Mr. Colin Walker of Stockport, England, and of the Haworthia Study Group, Cactus and Succulent Society of New South Wales, Australia.

Fig.1 H. margaritifera(L.)Haw. Karoo garden, Worcester. Three typical large plants.

Fig. 1. Haworthia margaritifera (L.) Haw., Karoo Garden, Worcester: three typical, large plants.

Fig. 2. Left: “H. poellnitziana Uitew.” 3m NW Drew.  Centre: H. minima Haw., S Bredasdorp, small coastal form.  Right: H. minima NE Riversdale, larger inland form.

Fig. 2. Left: “H. poellnitziana Uitew.” 3m NW Drew. Centre: H. minima Haw., S Bredasdorp, small coastal form. Right: H. minima NE Riversdale, larger inland form.

Fig. 3. Left: H. margaritifera (L.) Haw., 8 m. SE of Drew.  Centre: ‘H. poellnitziana’ 3 m. N.W. of Drew.  Right: “H. poellnitziana”  from the type locality at Drew.  Note keel at leaf tips, typical of H. margaritifera x marginata hybrids.

Fig. 3. Left: H. margaritifera (L.) Haw., 8 m. SE of Drew. Centre: ‘H. poellnitziana’ 3 m. N.W. of Drew. Right: “H. poellnitziana” from the type locality at Drew. Note keel at leaf tips, typical of H. margaritifera x marginata hybrids.

Fig. 4.  H. kingiana vPoelln., Great Brak.

Fig. 4. H. kingiana vPoelln., Great Brak.

Fig. 5.  H. marginata (Lam.) Stearn, a plant from N. Ashton.

Fig. 5. H. marginata (Lam.) Stearn, a plant from N. Ashton.

Fig. 6. “H. semiglabrata” Haw., a field hybrid H. margaritifera x marginata collected N. of Ashton.

Fig. 6. “H. semiglabrata” Haw., a field hybrid H. margaritifera x marginata collected N. of Ashton.

Fig. 7. Diagramatic presentation of typical base and profile of flowers in the subgenera (a) Haworthia (top, (b) Hexangulares Uitew. (middle), and (c) Robustipedunculares Uitew. (bottom).

Fig. 7. Diagramatic presentation of typical base and profile of flowers in the subgenera (a) Haworthia (top, (b) Hexangulares Uitew. (middle), and (c) Robustipedunculares Uitew. (bottom).

Anguish Among the Haworthias. (1972)

Printed in Cactus and Succulent Journal of Great Britain, 1972.

M. B. Bayer, Karoo Botanic Garden, Worcester, South Africa

Confusion in nomenclature has robbed an attractive and interesting genus of much of its charm and enticement to the collector. For the past few years considerable effort has been made at the Karoo Botanic Garden at Worcester, South Africa, into the investigation of Haworthia. It has been disturbing to find the extent to which current nomenclature is at variance with the natural groups as they are found in the field. Perhaps more disturbing is the difficulty which obviously lies in reducing the complex field relationships to an understandable and usable system of classification, Haworthia can clearly be divided into three subgenera on the basis of floral characters; these are the subgenus Haworthia in which the base of the floret is rounded-triangular and in which the outer three segments completely enclose the three inner ones, and the subgenera Hexangulares Uitewaal and Robustipedunculares  (Uitcw.) Bayer in which the floret base is rounded-hexangular (the florets stipitate in the former) with the outer floral segments separated by the midribs of the inner segments.

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Natural Variation and Species Delimitation in Haworthia Duval. – Part 1. HAWORTHIA RETICULATA (Haw.) Haworth (1972)

Printed in National Cactus and Succulent Journal, 27:10(1972).
Part 1. HAWORTHIA RETICULATA (Haw.) Haworth
M. B. Bayer, National Botanic Gardens of South Africa, Karoo Gardens, Worcester.

Abstract:  The name Haworthia reticulata (Haw.) Haw. is upheld for a species occurring in close association with H. herhacea (Mill.) Stearn in the Robertson Karoo.  Evidence is presented to show that H. haageana v. Poelln., H. hurlingii v. Poelln. and H. intermedia v. Poelln., together with published varieties of these, have their origin in the same species complex.  These species are reduced to synonymy in the single species H. reticulata.  It is suggested that H. subregularis Baker may also be synonymous.

Introduction:  There is reason to believe that the nomenclature in Haworthia is often not compatible with the distribution and variability of species of this genus as they occur in the field.  The object of this paper is to clarify the name H. reticulata (Haw) Haw. and apply it to field populations.

When Haworth originally described the species under the name Aloe reticulata, no exact locality was given.  Ker-Gawler published a description, accompanied by a coloured plate, of a plant which he named A. arachnoidea Burm. var. reticulata (Haw.).  Haworth (1812) apparently accepted the plant illustrated as conspecific with his species when he reinstated it as Haworthia reticulata.  As no type of his species appears to exist among Haworth’s specimens (Fielding-Druce Herbarium, Oxford), the plate t.13l4 in Curtis’ Botanical Magazine is regarded as the most acceptable neotype of H. reticulata (Haw.) Haw..

Jacquin (1804) described A. pumilio which, from the illustration, is considered to be nearer to H. herbacea (Mill.) Stearn than to H. reticulata because of the compact growth habit. Ker-Gawler (1811) erroneously included Jacquin’s species in synonymy with his A. arachnoidea Burm. var. translucens (Haw.) and Haworth, without seeing Jacquin’s description, followed suit when he reinstated H. translucens Haw.  Salm Dyck (1817) incorrectly allied Jacquin’s species with H. reticulata.

There is little doubt that the plant depicted by Ker-Gawler is associated with natural populations occurring in the Robertson Karoo.  Von Poellnitz (1938) recorded the distribution as ‘Worcester, Robertson and Swellendam districts and perhaps also in the Port Elizabeth district, but perhaps not in the Grahamstown district.’  G. G. Smith (unpublished data) cites Schonland’s identifications recorded in the Albany Museum Records (254, 1907-13). These identifications are certainly incorrect as the specimens are from the H. cymbiformis Haw. complex of the E. Cape.  This is also possibly true of H. subregularis Baker.  As a result of intensive field investigations into the variability, distribution and affinities of Haworthia in the Robertson Karoo, it can be positively stated that this is the locality for H. reticulata and that several more recent names and varieties are superfluous.  These are mostly species published by von Poellnitz, and it appears that either no type specimens as such were preserved, or they did not survive the bombing of Berlin.  Consequently his names can only be typified by single photographs in the Botanical Museum, Berlin-Dahlem, or as published with the species descriptions.  Some of these photographs are of poorly grown plants and, like pressed and dried material, often do not give an adequate impression of the living plant.  Fortunately it has been in some instances possible to determine the type localities with a fair degree of certainty and these have been thoroughly investigated.  Where species have been adequately illustrated at publication, and locality determined, no further reference to types has been made.

It is well-known that von Poellnitz received much of his material through W. Triebner in South-West Africa.  It is also generally accepted that errors occurred which resulted in localities for collections being transposed or confused, and in collections being attributed to the wrong collectors.  A frequent error is one in which the town from which plants were sent to Triebner by collectors is cited as the locality at which the plants were actually collected.  One such instance involves H. intermedia v. Poelln., which was described from McGregor where the collector, Mr. G. J. Payne, lived.  The actual locality given by Payne (private communication) is the farm Buitenstekloof near Langvlei, Robertson.  Originally the species was described with flower unknown, and when von Poellnitz later (1938) added a descnption’of the flower and the second locality, Scottburgh Farm, Port Elizabeth, it became certain that a second species is involved.  This is substantiated by the description and photograph of a species published under the name H. intermedia v. PoelIn. by  J. R. Brown in the American Cactus & Succulent Journal, which is clearly not the same plant as that from Buitenstekloof.

Field investigation:  Collecting was done throughout the Robertson Karoo and adjoining areas.  Reference was also made to records and photographs compiled by G. G. Smith and to preserved material in the Compton (NBG) and Bolus (801) herbaria.  H. reticulata was found in close association with other species elements and in some localities hybridising with these to form hybrid swarms.  The collections KG696/69 and KG178/70 involved such hybrid swarms; the former with H. herbacea and the latter with H. notabilis v. Poelln.  The collection KG159/70 includes forms which tend towards H. herbacea, but does not appear to be of direct hybrid origin as in the case cited.  It was noted that there was an apparent reduction in average plant size from west to east.  Each population was also found to be variable, including compact forms with shorter, as well as forms with longer, acuminate leaves.  Marginal denticulation was variable, with occasional forms almost totally glabrous.  Even in such forms, however, the keel was minutely denticulate at the leaf apex.  At the type locality for H. hurlingii v. Poelln. (KG654/69, 47/70) the plants were smaller than normal and the rosettes short-leaved and compact.  The leaf tips were sometimes not incurved, simply because the leaves were too rounded and turgid.  Similar forms were found to be common at the site KG690/69 and also observed at the site KG662/69.

The site KG105/70 at Buitenstekioof was regarded as having a typical variable population, and with the correction in locality, H. intermedia must be excluded as a valid species.  Two collections were made south of Bonnievale (KG221/70, 222/70) and it was difficult indeed to determine in which species these should be classified.  The leaf and rosette arrangement suggest H. herbacea, but proliferation, growth habit and flower are more nearly allied to those of H. reticulata, where they are therefore placed.  These collections also cannot be considered without reference to forms which occur in the hybrid swarm between H. reticulata and H. notabilis at KG78/70.  There are specimens from the Bonnievale area in herbarium collections which cannot be positively referred to either H. herbacea or H. reticulata, but as the former species has not been collected this far east, it is assumed that they are from the same population sampled south of Bonnievale.  H. guttata Uitew. is described from between Robertson and Bonnievale and there is a suggestion that this is only a form in the H. reticulata complex, especially in view of the forms occurring south of Bonnievale and in the hybrid swarm.  However, it is more likely that this species was drawn from a series of plants which appear to be allied to H. schuldtiana and further investigations into the relationships between these species are required.

As von Poellnitz related H. integra v. Poelln. with H. reticulata, it was thought that this species may also have had its origin in the Robertson Karoo.  In the Fourcade photographs (Compton and Bolus Herbaria), based on F. R. Long’s collection, photograph no.28 is said to be of type material but bears no relationship to any of the species discussed here.  Photograph no.244, also labelled H. integra. is undoubtedly of H. batesiana.  As most of Long’s collection was named in association with von Poellnitz, some weight needs to be given to the Fourcade photographs.

G. G. Smith identified a plant from Tweefontein, near Worcester, as H. subregularis Baker and suggests that this species is synonymous with H. haageana v. Poelln.  The illustration by Baker (1870) of the flower of H. subregularis supports this view.  The bud-tips are, however, drawn entire and the leaves somewhat cymbiform.  While it is strongly suggested that this species is merely a variant of H. reticulate,  reduction to synonymy may be premature.  Further consideration needs to be given to the possible alliance of H. subregularis to H. cymbiformis Haw. occurring in the East Cape.

Discussion:  During the investigation of Haworthia reticulate, 107 separate collections of Haworthia were made in the Robertson Karoo alone.  The various species elements are differentiated into localised populations, in many cases with precise ecological requirements.  In Haworthia pollination is by insects and the extent of spatial separation of conspecific populations suggests that interbreeding does not occur.  Thus most species seem to exist as a series of physiologically and perhap genetically distinct races, each in a particular ecological situation.  As hybridisation occurs very readily in cultivation across even the more easily recognised species, there is no suggestion that these ecotypes are fixed genetically.

It is clear that a species concept based on leaf shape and arrangement alone is unlikely to produce a satisfactory classification, as this will tend to be a narrow concept to accommodate ecotypic differences.  Conversely, a wider concept may preclude use of the more obvious foliage characters because of this same variability.  It does appear that geographic factors are of considerable significance and that river drainage systems and topography may form an essential basis for deciding species limits.  Thus, one would expect to find species most clearly differentiated in the higher inland areas of the drainage systems and introgression at the lower confluences.  This seems to be the case with H. herbacea and H. reticulata.  The latter occurs primarily on south-facing slopes of the Langsberg foot-hills and north of the Breede River, while H. herbacea is widespread in the area south of the Breede River and west of the westerly limits of H. reticulata.  Anomalous populations occur between these limits along the Breede River of Robertson and, together with the riverine Bonnievale populations, may represent the results of species introgression or, alternatively, may be ancestral forms from which the two species descended.  More evidence is required to substantiate these observations and this is not likely to be forthcoming until characterisation of species is more adequate in the genus.  There can be no doubt that geographic considerations must figure prominently in the creation of species concepts.

Conclusions:  The variability and distributions of each of the local populations sampled in this investigation invalidate the taxa H. haageana, H. hurlingii and H. intermedia, all of which are reduced to synonymy under H. reticulata:-

Haworthia reticulata (Haw.) Haworth, Syn. P1. Succ., 94 (1812) and Revis. P1. Succ., 57 (1821).
Aloe reticulata Haw. in Trans. Linn. Soc. Lond., 7:9 (1804).
Aloe arachnoidea Burm. var. reticulata (Haw.) Ker-G in Curtis’s Bot. Mag., t.l3l4 (1810).
Aprica reticulata (Haw.) Willd. in Berl. Mag. 5:272, nl7 (1811).
Haworthia haageana von Poelln. in Fed. Rep. 28:104 (1930).
Haworthia hurlingii von Poelln. in Fed. Rep. 41:202 (1937).
Haworthia intermedia von Poelln. in Kkteenk. 9:134 (1937).

The species is typified by Ker-Gawler’s illustration in Curtis’ Botanical Magazine, t. 1314 (1810).

Description:  Rosette acaulescent, 3-8cm diameter, up to 40 leaves.  Stem thick, white-fleshed, non-fibrous, up to one third of the diameter of the rosette, frequently elongate, proliferous from leaf axils or short stolons.  Roots thick, firm, white-fleshed, non-fibrous.  Leaves erect, spreading, incurved at tips, firm, up to 6Omm long, 20mm wide, 8mm thick, oblong-lanceolate acuminate, sometimes mucronate or subapiculate;  terminal bristle up to 2mm long; very pale to bright green, reddish in sun when dry, reticulated;  face concave at base, convex turgid towards middle and tip;  back convex, lightly keeled towards tip, keel denticulate;  margjn. rounded, denticulate, occasionally smooth, often pellucid; denticulae less than 1mm long, about lmm apart.  Perianth pinkish-white to very pink, tube ascending, curved, up to 19mm long, obclavate, triangular at base, 4mm across reducing to 3mm;  segments free, of outer tube valvate, inner tube imbricate, with upper limb cochlear, regular stellate, obtuse, not revolute, recurved to 90°, upper outer segments slightly plicate at tips, inner lower segments slightly incurved at extreme tips only.  Buds biarcuate, bifid at tips.  Flowering period August – October.

The collections cited in this paper are Karoo Garden (KG) collections, now in cultivation at Worcester, South Africa. The localities of cited collections are as follows:-

KG696/69 – Orange Grove, de Wet, Worcester.
KGl59/70 – One mile S.W. of Robertson.
KGl78/70 – Wolfkloof, Robertson.
KG654/69 & KG47/70 – 11 miles from Robertson towards Bonnievale.
KG105/70 – Buitenstekloof, Worcester.
KG221/70 – 1.5 miles south of Bonnievale
KG222/70 – 3 miles SE. of Bonnievale

Acknowledgement. The writer wishes to thank Mr. F. J. Stayner, Curator, Karoo Gardens, Worcester, for his contribution, assistance and encouragement during the course of this investigation.  He also wishes to acknowledge constructive criticism and changes suggested by Mr. C. Walker, and gratitude is also extended to Mr. J. Rourke of the Compton Herbarium, Kirstenbosch. for invaluable comment and criticisms.

Literature cited:
von Poellnitz, K., Fed. Rep. 33:239 (1933), Baker, 3. G., Saunders Ref. Bot. 4: t.232 (1870), Dodson, J. W., Haworthia Review 2:H-048 (1948).

Fig. 1.

Fig.1. KG 216/70 Ribbokkop (Photograph by Mr. F. J. Stayner).

Fig. 2.

Fig. 2. KG 216/70 Ribbokkop (Photograph by Mr. F. J. Stayner)

Fig. 3.

Fig. 3. KG 175/70 Le Chasseur (Photograph by Mr. F. J. Stayner)

Fig. 4.

Fig. 4. KG 143/70 Nonna (Photograph by Mr. F. J. Stayner).

Fig. 5.

Fig. 5. KG 119370 Effata (Photograph by Mr. F. J. Stayner).

Fig. 6.

Fig. 6. KG 159/70 Robertson (Photograph by Mr. F. J. Stayner).

 

Fig. 7.

Fig. 7. Haworthia reticulata (Haw.) Haworth. Illustrated by Ker-Gawler in Curtis’ Botanical Magazine,1-32; 1314,t.1314 (1810).

 

Natural Variation and Species Delimitation in Haworthia Duval. – Part 2. HAWORTHIA HERBACEA (Miller) Stearn. (1972)

Printed in National Cactus and Succulent Journal, 27:51(1972).
Part  2. HAWORTHIA HERBACEA (Miller) Stearn.
M. B. Bayer, National Botanic Gardens of South Africa, Karoo Gardens, Worcester.

Abstract:  The application of the name Haworthia herbacea (Mill.) Stearn to field populations is discussed.  It is concluded that this name applies best to the predominant complex occurring in the western and south-western Robertson Karoo.  The species H. aegrota v Poelln., H. submaculata v Poelln., H. luteorosa Uitew. and the variety H. pallida var. paynei are shown to have their origin in the same complex, and are therefore reduced to synonymy.

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Natural Variation and Species Delimitation in Haworthia Duval. – Part 3. HAWORTHIA REINWARDTII Haw. and HAWORTHIA COARCTATA Haw. (1973)

Printed in National Cactus and Succulent Journal, 28:80(1973).
Part 3. HAWORTHIA REINWARDTII Haw. and HAWORTHIA COARCTATA Haw.
M. B. Bayer, National Botanic Gardens of South Africa, Karoo Gardens, Worcester.

Abstract:  The names Haworthia reinwardtii Haworth and H. coarctata Haw. are upheld for two related species occumng in the Eastern Cape, South Africa.  The species names H. fulva Smith, H. musculina Smith, H. baccata Smith.  H. peacockii Baker and H. coarctatoides Resende et Viveiros are rejected as superfluous.  H. coarctata subsp. adelaidensis (Von Poellnitz) Bayer stat.nov., H. coartata subsp. coarctata var. greenii (Baker) Bayer stat.nov. and H. coarctata subsp. coarctata var. tenuis (Smith) Bayer stat.nov. are the only infra-taxa recognised.  The many varieties of H. reinwardtii previously upheld are, recognised as forms within the two accepted species. A map showing the distribution of the taxa is given.

Introduction:  Considerable doubt most exist that all the varieties of H. reinwardtii Haw. are really necessary.  Unfortunately such doubts are seldom associated with a rationalised expectation of what varietal differences should express.  It has already been shown that problems in Haworthia taxonomy can only be resolved by the adoption of a realistic species concept.  The object of this paper is to report on the field investigation into the distribution and variation of H. reinwardtiii and its allies, with observations on population structure within this complex.

The species involved in this study are all in the Section Coarctatae Berger, and include H. baccata Smith, H. coarctata Haw., H. coarctatoides Res. et Viveiros, H. fulva Smith. H. greenii Baker, H. musculina Smith, H. peacockii Bak., H. reinwardtii and varieties of these.  Apart from Smith’s species, original localities are not recorded.

Investigation:  Attention was confined to the Eastern Cape, in the area extending from Addo in the west to East London in the east, and from the southern sea coast to the Fish River in the north.  As for other species of Haworthia, it was found that plants are nearly always confined in small localised populations of varying densities.  No particular correlation of distribution with vegetation type or geological formation was observed, and plants were recorded from sea-level to 650m through four main vegetation types and three geological systems.  Distribution is primarily associated with rocky, well-drained situations and reduced competition from other vegetation.  This latter point is by no means always true, as for example H. reinwardtii var. tenuis Smith, growing in deep soils under a dense canopy of Valley Bushveld vegetation.  Similarly, as the name implies the origin of H. greenii var. silvicola Smith was also sylvan.  Fifty-three collections were made at different points throughout the area, paying particular attention to localities for recognised varieties where known.  Of these, only H. reinwardtii var. peddiensis Smith was not recollected.  In each case up to ten pieces of full- length leafy stem were collected from separate plants at each site.  Judgement of the taxonomic position is thus based on field impressions, collections made personally by the writer, twelve collections made by Mr F. J. Stayner, 31 single plant collections still extant in Smith’s collection after 30 years, and on herbarium specimens in the Albany Museum, Grahamstown, the Compton Herbarium, Kirstenbosch and the Bolus Herbarium, University of Cape Town.

Attention is drawn to specimens in the Bolus Herbarium; H. Viedge April 1927 from “Tabase’ near Umtata”, a sparsely tubercied and steeply spiralled plant like H. coarctata, R. C. Holmes August 1935 from ‘between Kei and Tsomo Rivers” which is akin to H.. attenuata Haw., and a glabrous leaf remnant, Pillans November 1906, from “between King Williamstown and Grahamstown”.  Neither of the latter specimens can be confidently allied to present known taxa, and the Umtata specimen in particular represents a complete contradiction in terms of the known distribution of the genus.

In the case of H. baccata. a thorough search was made in the Isidenge area of the Stutterheim district before concluding that the locality was a most improbable one.  It was subsequently learned from Mr W. E. Arrnstron (a well-known collector) that the plant had not been collected at Isidenge but in fact came from Frazers Camp near Grahamstossn.  The plant came in Smith’s possession at third-hand and there is thus reason to question the given locality.  Interpretation of observations presented here was subject to particular consideration of both phenotypic and genotypic variation.  Phenotypic variation is the outward appearance of the individual as it responds to factors in the environment.  Comparison of specimens collected from the same sites as plants growing in Smith’s collection showed surprisingly little differences.  Attenuation resulting from shading was seldom encountered and it was nearly always possible to observe plants at each locality in demonstrably steady growth states.  More difficult were certain localities where combinations of rock substrate and shade produced more variable growth conditions.

As far as the genotype – the fixed genetic basis of variability – is concerned, the problem also appears relatively slight, despite the high percentage of polyploidy noted by Riley (1968).  Riley suggested that polyploidy may account for the large number of taxonomic varieties in H. reinwardtii, or alternatively because differences between these are small, that they may have arisen as single gene mutants which have propagated vegetatively.  Riley and Mukurjee (1965) recorded 4 diploids, 8 tetraploids and 1 aneuploid.  These are H. fulva, H. reinwardtii vars. olivacea Smith, tenuis Smith, haworthia Res. (= reinwardtii) with 2n =14; H. baccata, H. musculina, H. greenii var. silvicola, H. reinwardtii vars. huntsdriftensis Smith, valida Smith and an unnamed variety with 2n=28:

and H. greenii forma pseudocoarcata (VP) Res. with 2n=28 and 30.  In 1962 (Riley,1968) these authors also recorded the aneuploid H. reinwardtii var. chalwinii (Marl. et Berg.) Res. with 2n=26.  Resende and Pinto-Lopes (1946) recorded the following: H. reinwardtii vars. adelaidensis VP., triebneri VP, minor Haw. and major Haw. 2n= 14:  H. reinwardtii vars. conspicua VP, fallax VP, haworthia, chalwinii, H. greenii forms greenii, minor and pseudocoarctata 2n =28:  H. reinwardtii var. archibaldiae VP 2N=21;  H. coarctata vars. coarctata, kraussii Res. and coarctatatoides Res. et Viv. nom. nud. 2n=42.

Where these records can be referred to field populations, it appears that diploids and polyploids are encountered across the range of the species complexes.  Thus polyploidy is not conclusively a basis of species or varietal differentiation in this group.  If it were so, one would expect some evidence of discrete sympatric populations – which is definitely not the case for example, at ‘Hopewell’, Bathurst. Here H. fulva, H. musculina and H. greenii var. silvicola all have their origin in the same close locality.  Smith’s field notes, in which he also recorded H. coarctata, H. chalwinii and H. reinwardtii from the same locality, put the three taxa into proper perspective.  Apart from the fact that H. musculina and H. greenii var. silvicola have been cited as tetraploids, as opposed to H. fulva which is diploid, these three taxa do not command separation if indeed recognition at the level of forms. H. coarctatoides is a nomen nudum for a plant said to be intermediate between H. reinwardtii and H. coarctata and can be rejected as a meaningless taxon.

Only one locality was found presenting any real evidence of two non.-interbreeding entities growing together.  This is at Hellspoort where one of these entities is allied to H. coarctata and may thus be hexaploid (or perhaps only tetraploid following Resende’s notes on the locality for H. greenii forma pseudocoartata at Alicedale, a plant which the writer allies with his interpretation of H. coarctata), and the other to H. reinwardtii var. adelaidensis which is diploid.  The latter variety can be shown to be correctly related to H. coartata at subspecies level.  An interesting point is the occurrence of sterile or at least partly sterile triploids in the H. reinwardtii vars. archibaldiae. chalumnensis Smith and peddiensis (Riley, private communication).  The writer particularly noted two populations in which it appeared that despite normal flowering, ovules were aborting.  This does bear on Riley and Majumdar’s (1966) statement that Haworthias usually propagate vegetatively.  While as a general stalement this is incorrect, it is clearly to some extent true for some species including H. reinwardtii and H. coarctata.  Vegetative reproduction could perhaps account for uniformity at different sites if populations had their origins in single clones, or alternatively one would expect more discontinuity where several genotypes were involved.  Variability at various sites and clinal trends across the distribution range, in the writers opinion,  tend to detract from vegetative propagation as a factor in population differentiation.  In support of this comment is the observation on locality restrictions where it is felt that movement of detached stems would surely lead to positive downward migration of populations.  Yet it is a feature of the species, particularly nearer Grahamstown and notwithstanding earlier comments, that they occupy elevated positions on edges of ridges and plateaus.  Nevertheless there is adequate evidence that vegetative propagation does occur especially under conditions of heavy grazing.

A final consideration is the exploratory work done by Riley and Isbell (1963) on paper chromatography in the Aloineae.  Here it was suggested by way of demonstration that H. fulva was close to H. greenii, that H. reinwardtii vars. tenuis. committeesensis Smith and possibly diminuta Smith were close, that H. reinwardtii vars. haworthii and chalwinii were similar, whereas the vars. archibaldiae, valida and H. baccata were different.  If H. baccata had originated at Frazer’s Camp, the chromatograph could have been expected to show affinity to H. reinwardtii var. diminuta.  Similarly on the basis of distribution and outward appearances, one would have expected diminuta to be at variance with, rather than relating to committeesensis and tenuis: the latter two also expectedly differing to some degree.

Results and Discussion:  The superficial impression that might be gained from the field is that a single species complex is involved.  However, three distinct entities, with the two larger of these exhibiting strong clinal trends, are apparent.  The two principal entities are regarded as H. coarctata and H. reinwardtii and it is rather surprising that there is a complete break in continuity between them despite their close affinity.  Conceptions based on past taxonomic treatment give no indication of this discontinuity, and varieties previously described under H. reinwardtii actually belong in H. coarctata as will be shown.  Even the older species H. chalwinii resolves under H. coarctata rather than H. reinwardtii as implemented by Resende.  Most existing taxa in the complex are based on size, density of leaf arrangement and on shape, size and arrangement of leaf tubercles.  That these criteria are inadequate is clear both front examining variability within and between populations. and from the relation of the described taxa to one another and to field populations.

In attempting to rationalise the discontinuity between eastern and western populations in the complex, it was concluded that the general difference as associated with the spiral arrangement of the leaves on the elongated stems – a principle of phyllotaxis elaborated by Church (1904).  (Church postulated that phyllotaxis is a result of fundamental growth processes and can be treated mathematically.)  It is this phenomenon of spiral series which provides the device by which the two entities can be consistently and satisfactorily differentiated.  By cutting the leaves at right-angles near (4mm) to the stem, these spiral rows (parastichies) can be more clearly observed.  In the entity H. coarctata there are apparently 2 spirals ascending in one direction with approximately 4.5 leaves per revolution, while in the reverse direction there are 3 spiral tiers with 7 leaves per revolution.  In the entity H. reinwardtii, 3 spirals with 7 leaves per revolution and 5 counter spirals with 11 leaves per revolution are seen.  In fact, in both entities the leaves are arranged in a single continuous spiral about the stem, so that cutting the leaves too close to the stem precludes the configuration stated here.  In both species, the leaves follow successively at an angle of approximately 137.5 degrees, so that the 22scd leaf in the spiral is again superposed over the first (the orthostichy) through 8 revolutions.  The difference in spiral patterning is thus apparently an artifact which is dependant on a number of variables.  These are: the ratio of stem diameter to leaf width, leaf thickness, degree to which the leaves are amplexicaul. (in effect Church’s ‘bulk ratio’), the degree of compression of the spirals on the stem, and the angles at which the leaves are subtended from the stem.  The ratios of stem diameter to leaf width in H. coarctata and H. reinwardtii are 1:1.7 and 1:1.16 respectively (see table 1).  The real nature of the spiralisation of leaves is shown in diagram I and 2.  In H. coarctata the tiers seen on the cut leaf sections are the 3 tiers of the secondary spiral (P2 on diagram) and the 2 tiers of the primary counter spiral (Cl).  In H. reinwardtii it is the 3 tiers of the secondary spiral and 5 tiers of the secondary counter spiral (C2) which are seen: the primary counter spiral ascending at such a shallow angle that the narrower leaf sections comprising it are taken for the primary spiral.  The angle of ascent of the primary spiral in H. reinwardtii is half that in H. coarctata, and it is interesting to note that the maximum stem length of 26cm observed in the field, was also almost half of the 47cm observed in H. coarctata.

It must be stressed that growing conditions may possibly affect the angles of ascent of the leaf spirals to some degree, so that thicker, fleshier leaves in a specimen of H. reinwardtii may produce a likeness to a specimen of H. coarctata grown under hardy conditions. In the writer’s experience of the plants in the field and under cultivation, the distinction between the two species on this basis is absolute, and it is confidently expected that a statistical evaluation of stem and leaf dimensions will verify this conclusion.  It should be noted that in the section Trifariae. the 3 leaf spirals are the secondary spirals (leaves 1-4-7- . . . ). In Astroloba and Poellnitzia, the 5 spirals are secondary counter spirals (leaves 1-6-11- . . . ).  A plant of H. margaritifera (L.) Duv. at the Karoo Garden has the leaves in 8 spirals – the tertiary spirals (1-9-17- . . .), while even the distichous leaves in H. truncata Schon. are arranged in a spiral series (the primary counter spiral!  The leaves are arranged spirally in all plants and whether the spirals impress visually or not depends on the width and thickness, curvature, nature of attachment, and density of the leaves on the plant stem.

The distribution of the principal entities recognised in the present study is shown in the accompanying map.  In H. coarctata, very large forms exist as populations in the vicinity of Patterson, Alicedale, Hellspoort and Fort Brown.  Intermediate forms occur south and west of Grahamstown. and smaller forms in the Bathurst-Alexandria area.  The Hopewell population is not such an extremely heterogenous one as earlier notes suggest, and localities on the Kowie River at Vaalvlei and at Blaauwkrantz Bridge near Manley Flats display perhaps greater variability.  H. reinwardtii var. tenuis represents a distinct discontinuity and is upheld in the species H. coarctata, in the absence of further known populations, at varietal level.  H. fulva, H. musculina and H. reinwardtii var. committeesensis do not represent marked discontinuities, and the same is true of H. reinwardtii var. chalwinii. The latter appears to be an admittedly rather di€tinctive form, but which appears in various population of H. coarctata including the entity tenuis.  H. greenii at Howiesonspoort is recorded as both tetraploid and aneuploid and is a notable variant although clear population discontinuity does not occur.  Its tetraploid state does not necessarily suggest taxonomic separation from the main body, H. coarcata, where diploid to hexaploid states are known.  H. peacockii with its submersed tubercies is considered to be a local variant at Howiesonspoort and is rejected taxonomicall, while H. greenii is upheld at varietal level only.  With the rejection of H. chalwinii at any level above that of forma, H. coarctatoides receives similar treatment. H. reinwardtii var. conspicua is rejected as a form of H. coarctata as many plants agreeing reasonably with Von. Poellnitz’ description were seen, but not constituting discrete populations.

H. reinwardtii var. huntsdriftensis Smith represents something of an anomaly.  In the Compton Herbarium, Smith 6818A from “n hill at top Hunt’s Drift, last cutting on west side of Fish River” is clearly H. coarctata, as is Smith 7105 – “top Hunt’s Drift, west side”.  Smith 6818 and 68l8B are from “on hill on top of Huntsdrift just before valley before Frazers Camp”, and these may be specimens of H. reinwardtii.  Smith 3849 “west side of Hunt’s Drift” is an isotype and Smith 7106 “top Huntsdrift near Frazers Camp” is very similar.  There is in all cases a lapse of 4-5 years between collection date and herbarium labeling except for Smith 7106, one year.  If Smith’s detailed locality for the variety “in hollow before last hill going up to last gate at top Hunt’s Drift” is correct, then plants collected by the writer at this locality are at variance with the described taxon.  Either this is due to (a) phenotypic changes brought about by cultivation—which is discounted, (b) errors between collection and recording – and there are six herbarium sheets involved, or (c) there is an additional point not located by the writer where H. coarctata is in close proximity to H. reinwardtii.

The question of phenotypic change is rejected as almost without exception herbarium specimens agree with current field collections.  Exceptions are one specimen labelled “25 miles from Port Alfred to Alexandria”, which is the actual distance between these towns; and the specimen agrees with plants of H. reinwardtii collected at a distance of about 5 miles along that road.  Another exception is Smith 7349 labeled “4-5 miles between Riebeek East and Alicedale” which is a blatant misfit, matching rather specimens from the eastern limits of the distribution of H. reinwardtii and Smith 5218, an isotype of H. reinwardtii var. riebeekensis Smith, labelled “4 miles before Riebeek East from Alicedale” whereas in Smith’s field book the locality is recorded “4.5 miles before Riebeek East from Carlisle Bridge”.  These few discrepancies in all the herbarium specimens (263 sheets) do not allow the supposition that either phenotypic change or incorrect labeling are responsible.  Plants which do match Smith’s description occur at Hunt’s Drift on the east bank, and it is likely that they are also found nearer Frazers Camp.  This may prove important in future studies on this group.  H. reinwardtii var. huntsdriftensis is considered to belong to H. coarctata.

H. reinwardtii var. bellula Smith is another anomaly, as a close search of the type locality, and near localities, failed to produce matching specimens.  What very small specimens were seen were taken to be suffering under adverse growth conditions, and the population at this locality falls into a series extending from Bothas Ridge and Queens Road northeast of Grahamstown, to Hellspoort and Riebeek East.  The Queens Road locality is the type locality for H. reinwardtii var. adelaidensis VP as pointed out to Smith by the finder, W. F. Armstrong.  This is one of Von Poellnitz’ unfortunate errors where a locality has been attributed to the collector’s address rather than to actual field origin.  At Hellpoort there is the case of a smaller, densely-leaved entity coexisting with a more typical population of H. coarctata, albeit not precise superimposition of locality. This fact coupled with morphological criteria, is the basis for recognition of the taxon H. coarctata. subspecies adelaidensis, which includes the populations from which the H. reinwardtii vars. bellula and riebeekensis were drawn.  In the latter case, Smith’s field notes were found to be confusing and the site at Willowfountain north of Riebeek East could only be located by cross reference to noted landmarks and two other species recorded from the near vicinity.

Generally in H. coarctata the tubercles are nearly smoothly rounded and smaller than in H. reinwardtii, where they are frequently large and flattened scale- like.  Also in H. coarctata there are more tubercles across the width of the leaf than in H. reinwardtii.  Between Salem and Alexandria, southwest of Grahamstown, there is one particular population of H. coartata with much larger tubercies and also very densely tubercled on the leaf face.  However, this is not clearly discontinuous if other populations are also considered and a new taxon is not proposed.

The distribution of H. reinwardtii can be traced from Kaysers Beach near East London, to a point west of Port Alfred, then northward to Frazers Camp and Coombs and eastward to Peddie.  Local populations appear to some extent more consistent than in H. coarctata but discontinuities are not readily discernible. H. reinwardtii var. major is a form which can be found at several localities, and H. reinwardtii var. chalumnensis is reasonably regarded as one of these.  H. reiiiwardtii vars fallax, valida. kafferdriftensis Smith, pulchra VP and grandicula Smith similarly have no reasonable basis on the grounds of population discontinuities.  The same is true of the var. peddiensis which, in the absence of field material, it was necessary to compare the described taxon and the living type with populations nearer to the Fish River.  H. reinwardtii vars. zebrina Smith and olivacea Smith are distinctive forms in a notably variable population and it cannot be considered that rank above forma is necessary or desirable.  In the case of H. reinwardtii vars.brevicula Smith and diminuta, the taxa are drawn effectively from the same population at Frazers Camp.  If it was necessary to apply an appellation to this fairly extensive population, perhaps the name H. reinwardtii var. minor Baker would be more appropriate at the extreme of a clinal trend in size-reduction from southeast to northwest.

In H. baccata the specimen Smith 3572 (NBG) is an isotype dated July 1944 and agrees reasonably with Smith’s illustration.  Another isotype, Smith 3572 (BOL) dated November 1945 does not agree with the previous specimen, but does conform with specimens from Frazers Camp.  As Armstrong, who knew the collector, Mr McClaren, maintains that H. baccata originated at this locality, the name is rejected as superfluous.  The locality of H. reinwardtii var. archibaldiae is, on the basis of specimens submitted to Smith by Miss G. V. Britten (of the Albany Museum, and a contemporary of Miss E. Archibald), taken to be at the Umtana River east of Wesley in the Peddie district.  Only four clones were located in a brief search at this site and this scarcity may be attributable to it being a sterile triploid.  Smith identified several plants from other localities as this taxon and Von Poellnitz also recorded two localities – the varietal rank is not upheld.

Conclusion:  The separation of H. reinwardtii and H. coarctata on the basis of morphological criteria, also satisfies geographical requirements.  Local populations in each species, and particularly in H. reinwardtii, tend to have distinctive facies but discontinuities between populations are seldom marked.  It is the writer’s opinion that colouration and general condition of the plants, imposed by local environmental conditions contribute greatly to this phenomenon of local ecotypes, obscuring more basic similarities between populations.  A key for separation of varieties, as presented by Von Poellnitz, may have been workable in a collection comprised only of those particular forms, but not as a basis for usefully or consistently distinguishing field collected material.  The diagnoses by which the described varieties of H. reinwardtii were to have been distinguished from one another can often be totally discredited by inherent variability at each point of origin.  It is a basic tenet of taxonomy that all individuals must be referrable to a species.  If lesser ranks are recognised in these species, it is logical to expect that in the same way individuals will all be referable to these categories and the parent species not treated as a repository for all forms which do not conveniently agree with descriptions.

Believing that the present exposition satisfies these requirements, the writer’s concept of H. coarctata and H. reinwardtii is as follows:-

Haworthia coarctata Haworth in Phil. Mag. 44: 301 (1.824).
Aloe coarctata (Haw.) S-D. Monogr. S6, f. 17 (1836-49).
Haworthia chalwinii Marl. et Berg. in Notizblau Berl. Bot. Gart. 4: 247 (1906).
Haworthia reinwardtii var. conspicua VP. in CJ. 5:31 (1936).
H. reinwardtii var. committeesensis Smith in Jl SA. Bot. 9:93 (1943).
H. fulva Smith in 15.4. Jl SA Bot. 9:101(1943).
H. greenii var. silvicola Smith in Jl SA.Bot. 9:103 (1943).
H. reinwardtii var. huntsdriftensis Smith in Jl.S.A. Bot. 10:14 (1944).
H. reinwardtii var. chalwinii (Marl. et Berg.) Resende et Pinto-Lopez in Port. Acta Biol. (B) 2:175 (1946).
H. coarctatoides Res. et Lopez nom. nud. in Port. Ada Dial. (A) 2:175 (1948).
H. musculina Smith in JS.A. Bot. 14:43 (1948).

Plants with fibrous elongate leafy stems from 5 to 47cm long, overall diameter from 2 to 7cm; leaf length from 2.5 to 7.5cm, width from 1.0 to 2.4cm, thickness from 0.2 to 0.8cm;  ratio of stem diameter to leaf width in region of 1: 1.7; leaves ascending- spreading, multifarious incurved, broadly lanceolate to ovate-deltoid, broadly amplexicaul;  back of leaves rounded, slightly keeled above, beset with numerous small rounded tubercles;  face generally flat to concave, seldom tubercled.

Haworthia coarctata subsp. coarctata var. greenii (Baker) Bayer comb. nov. –
H. greenii Baker in Journ. Linn. Soc. 48:202 (1880).
H. peacockii Bak. in Journ. Linn. Soc. 48:202 1880.
Plants with stems up to 15 to 20cm long, overall diameter up to 5cm, tubercles mostly suppressed or absent.

Haworthia coarctata subsp. coarctata var. tenuis (Smith) Bayer comb. nov.
H. reinwardtii var. tenuis Smith in Jl.S.A.Bot. 14 :51 (1948).
Plants with narrow elongate stems up to 44cm. overall diameter 2.5cm, leaves up to 3.2cm long , 1cm wide.

Haworthia coarctata subsp. adelaidensis (VP) Bayer comb. nov.
H. reinwardtii var. adelaidensis VP in Succ. Afr. 3:82 (1943).
H. reinwardtii var. riebeekensis Smith in Jl. SA. Bot. 10:16 (1944).
H. reinwardtii var. bellula Smith in Jl.S.A.Bot. 11:70 (1945).
Plants with stems from 5 to 15cm long, overall diameter up to 3cm, leaf length 2.5 to 3.5cm, width 1.0 to l.lcm, thickness 0.2 to 0.3cm.  Leaves are proportionately longer and narrower than in type, while stems are more elongate and thinner overall than in corresponding specimens of H. reinwardtii.

Haworthia reinwardtii Haworth
Suppl P1. Succ., 57 (1819).
Aloe reinwardtii (Haw.) S-D. Monogr. S6, f16 (1836-49)..
H. baccata Smith in Jl.S.A. Bot. 10:20 (1944).
(Included in synonomy are the varieties of this species described at various times by Von Poellnitz, Smith and Resende which have not been located elsewhere.)

Plants with fibrous elongate leafy stems from 5 to 26cm long, overall diameter from 2.5 to 6cm, leaf length from 2 to 4.5cm. width from 0.7 to 1.5cm. thickness from 0.2 to 0.35cm;  ration of stem diameter to leaf width in region of 1:1.16.  Leaves ascending – spreading multifarious, incurved, lanceolate, narrowly amplexicaul;  back of leaves rounded, slightly keeled above, beset with large flattened scale-like white tubercles generally arranged in transverse rows, face flat, often sparsely tubercled.

(Note: It is proposed to maintain all specimens collected during the course of this investigation at the Karoo Botanic Garden, so that in due course the above classification can be verified or revised.  Floral morphology has not been considered as a source of characters as the similarity or floral structure in the subgenus Hexangulares Uitewaal suggests that a very meticulous, time-consuming study would be required to prove the worth as a taxonomic aid.  It is also suggested that the above arrangement based on vegetative characters may provide a working basis for further investigation in this complex.  For collectors it is suggested that deposed varieties be regarded as formae in the respective species, as there is no doubt that specimens such as ‘zebrina’ and ‘olivacea’ are striking collectors’ pieces.)

Acknowledgement:  The writer gratefully acknowledges the encouragement and assistance received from the Curator of the Karoo Garden, Mr F. J. Stayner, and also the assistance and hospitality of Mr D. A. Timm of Vaalvlei, Grahamstown, during the course of field work.

Literature cited:
Riley, H. P. The Nucleus, Seminar on Chromosomes (1968).
Riley,.H. P. and Mukurjee, D. The Nucleus 8:2 p. 149 (1965).
Riley, H. P. and Majumdar, S. K. Botanical Gazette 127:4 p. 239 (1966).
Resende and Pinto-Lopez, I. Port. Acta. Biol. (B) 2:178 (1946).

Fig. 1 Photograph of principal entities to show secondary spirals:- Left: KG 31/64 H. coarctata subsp. coarctata. Biaaukrantz Centre: KG 39/65 H. coarctata subsp. adelaidensis. Queens Road Right: GGS 7346 H. reinwardtii. east of Fish River
Fig. 1 Photograph of principal entities to show secondary spirals:-
Left: KG 31/64 H. coarctata subsp. coarctata. Biaaukrantz
Centre: KG 39/65 H. coarctata subsp. adelaidensis. Queens Road
Right: GGS 7346 H. reinwardtii. east of Fish River
Diagram 1. Diagram showing the different angles of the leaf spirals in (A) H. reinwardtii where the low angle of the secondary counter spiral approximates that of the primary spiral in (B) H. coarctata.
Diagram 1. Diagram showing the different angles of the leaf spirals in (A) H. reinwardtii where the low angle of the secondary counter spiral approximates that of the primary spiral in (B) H. coarctata.
Diagram 2. Diagram showing the position of the leaves relative to the stem axis and the spirals so formed. P2 - One of three secondary spirals Cl - One of two primary counter spirals 		C2 - One of five secondary counter spirals
Diagram 2. Diagram showing the position of the leaves relative to the stem axis and the spirals so formed.
P2 – One of three secondary spirals
Cl – One of two primary counter spirals
C2 – One of five secondary counter spirals
Diagram 3. Map showing the distribution of:- C - H. coarctata subspp. coarctata var coarctata Haw. CG - H. coarctata subspp. coarctata var greenii (Bak.) Bayer. CT - H. coartata subspp. coarctata var tenuis (Smith) Bayer. CA - H. coarctata subspp. adelaidensis (V Podia.) Bayer. R - H. reinwardtii Haw.
Diagram 3. Map showing the distribution of:-
C – H. coarctata subspp. coarctata var coarctata Haw.
CG – H. coarctata subspp. coarctata var greenii (Bak.) Bayer.
CT – H. coartata subspp. coarctata var tenuis (Smith) Bayer.
CA – H. coarctata subspp. adelaidensis (V Podia.) Bayer.
R – H. reinwardtii Haw.

Table 1.

Leaf spirals in Haworthia. (1973)

Printed in Aloe 11:31 (1973).
M. B. Bayer, Karoo Botanic Garden, Worcester.

The fascination of haworthia lies in the shape, arrangement, compact neatness and marking of the leaves.  With nearly 170 named species and over 200 varieties, the genus is unfortunately very confused as far as the application of these names is concerned.  Many of the species originally described by Haworth and Baker have not been recognised since, while in recent times new species have been described with little or no reference to occurrence, distribution and variation of existing or related species.  Obstacles in the way of better classification and recognition of the species are many, and include insufficient information on basic morphology.  Secondly, whatever morphological differences there might be between species are often difficult to rationalise and describe, and may even be difficult to perceive with the naked eye anyway.  A third difficulty is the whole question of framing an adequate species concept, or for that matter, a concept of sections.   There is at present even an illogical trend to ‘lump’ the genera Astroloba, Poellnitzia and Chortolirion, into Haworthia, showing that concepts at that level have not reached reasonable finality.  The removal of genera can be applauded for its broadmindedness, if singular lack of appreciation of (a) the criteria by which they can be recognised, or (b) the reasons why they were erected in the first place.  Such an approach must naturally descend to species level, and at a time when the birth pangs of ‘splitting’ and consolidation have barely started, can only lead to a loss of information.

The writer’s experience of the naming of Haworthias and also of other succulent plants, suggests strongly that species descriptions based on broad external appearances are often very inadequate.  Growing conditions including the influence of soil types, temperature, water and light may have such a strong influence on plant growth as to completely nullify the written description, particularly where based on single specimens as has so often been the case.  The object of this article is to discuss the leaf arrangement in Haworthia and its relationship to the general appearance of the plants.  As in many plants, the leaves are produced consecutively at the growing point of the plant, and are consequently arranged in a single continuous spiral about the stem (the genetic spiral).  Thus Aloe polyphylla is by no means unique with its leaf spirals.  When the leaf bases are wide and enfold the stem it is much easier to observe this spiralisation, but when narrowly attached on a broad stem it may be more difficult to detect.  Generally the leaf bases are not continuous as they are in A. broomii where the leaves may be detached from the plant in a long continuous ribbon.  The leaves are produced at a fairly constant angle subtended from the stem and the result is similar to that obtained say when an orchard is planted with the trees at equal distances in and between the rows – i.e. secondary rows are visible when the orchard is viewed from a different angle.   These secondary rows are called parastichies.  The very obvious 3- and 5-tier arrangement of the leaves in the Haworthia section Trifariae and in Astroloba are the result of secondary spiralisation and have long been recognised in taxonomy.  Similarly Haworthia retusa was originally defined as quinquefarious and H. truncata has always been distinguished by its distichous leaf arrangement.

Generally it seems in Haworthia that the twenty-second leaf is again approximately superposed over the first after 8 complete revolutions of the genetic spiral (leaf-divergence (8.360)/21=137 degrees).  However, in the Trifariae only three leaves are clearly visible when the plant is viewed from below and these leaves form the bases of the three secondary spirals which characterise the group.  The leaves are arranged in three tiers with the leaf sequences 1—4—7—10;

2—5—8—11; 3—6—9—12 (i.e. three parastichies).  The classic example of this trifarious arrangement is H. viscosa where every third leaf is superposed approximately over the first.  In the quinquefarious (5-tiered) spiral, the leaf sequence is 1—6—11—16; 2—7—12—17; 3—8—13—18; 4-9—14—19; 5—10—15—20 (five parastichies as in Astroloba), and in the octafarious 8-tiered) spiral 1—9—17—25; 2—10—18—26; 3—11 etc.

In long-stemmed species particularly, it is possible to see simultaneously the arrangement of leaves in tri-, quinque- or octafarious series e.g. in H. reinwardtiii and H. coarctata.  In the short-stemmed, broad- and few-leaved species such as H. retusa or H. pilifera (now H. cooperi), only the lower series are visible, whereas in the acaulescent, many-leaved species, the higher series may appear.  It may seem that the angle of divergence of the leaves from one plant of a species to another is a constant one.  This is not true for the writer has seen for example a single plant of H. rnargaritifera now (H. pumila) with 8 perfect vertical rows indicating a leaf-angle of 135°.  Normally in this species the parastichies 5 and 8 are seen ascending in opposite directions.  In H. tuberculata (now H. scabra) the leaves appear randomly arranged at some localities whereas at others the plants are either trifarious or both the 3 and 5 parastichies are apparent.  In H. viscosa one would expect that to achieve three near vertical leaf tiers, that the angle of leaf divergence must be 120°.  Actually the angles prove to be only complementary, being often on the order 135°, 115°, 110° – to the point that they can be accurately measured.  Similarly in a plant of H. sordida the angles were measured at 180°, 95°, 85°.  Despite the fact that no one angle is measurably the same as the next, the plants still age to maintain an orderly progession of leaves.  In H. truncata, which is distichous (and really only approximately so), the two rows of leaves are actually the consequence of a spiral arrangement in which the leaf angle is near to 180°.

In H. limifolia the average leaf angle is in the vicinity of 160° but this is by no means constant as Diagram 1 of the variety ubomboensis will show.  Some leaf pairs are almost opposed at 180° and the youngest 7 leaves have an average divergence of 170°.  What is perhaps important is that two parastichies are prominent – the primary counter spirals with the leaf sequences 1—3—5—7; 2—4—6—8.  The impossibility of accurately estimating the central axis in the plant from which to measure the angles of divergence must be stressed.  By counting the number of leaves in rotational sequence until a leaf directly above the first is reached, an estimate can be made; thus the ninth leaf above the first in 3 revolutions is the consequence of (3.360)/8= 135 degrees divergence.  Spiral patterning is also related to stem diameter in proportion to leaf thickness and width.  If the stem diameter is great and leaf width small then the higher parastichies will appear.  The relation of stem length to number and size of leaves will also affect spirals.  In H. reinwardtiii and H. coarctata, a complex notorious for its many varieties and forms, the two species with their discrete distribution ranges are separable almost only by the fact that the ratio of number of leaves to stem length differs.  Thus in H. reinwardtii the leaves are more densely compressed on the stem, there are more leaves per unit stem length and the angle of ascent of the genetic spiral is approximately half that in H. coarctata.  Oddly enough the longest stems observed in a recent field study were H. reinwardtii:  27 cm and H. coaretata: 49 cm.  An associated variable is the ratio of stem diameter to leaf width…1:1,7 in H. coarctata, and 1:1,16 in H. reinvardtii.

Diagram 1 illustrates the leaf arrangement in a single plant of H. limfolia var ubomboensis showing the two counter spirals very clearly.  Diagram 2 illustrates the situation in which a uniform leaf angle of 135° presents 8 vertical parastichies, and also how variations of 1—4° alter the entire conformation in only 3 revolutions of the genetic spiral.  At 139° five parastichies are becoming prominent which will reach the vertical at 144°, whereas at 131 °three parastichies will be dominant and reaching vertical at 120°.  A 1°  increase in leaf divergence will result in an 8° displacement at the ninth leaf.

A.H.Church in a fascinating book… “On the relation of phyllotaxis to mechanical laws” (1904), explains that there is a fundamental constant which determines leaf arrangements and spiralisation.  He defines this as the “bulk-ratio”, which is the ratio of the diameter of the leaf buds to the diameter of the stem at the point at which they are joined to it.  In this light, raw dimensions (especially from single plants) can be seen as only a fractional contribution to species descriptions.  Where even normal standards of biometry have been ignored it is even more important to appeal for a more realistic use of measurements.  While proportionate dimensions of leaves and stem (ratios between leaf width, leaf thickness and stem diameter, for example) may help to better describe a species, it does not mean that the basic problem of defining the species will be solved.  In Haworthia the populations are so localised and often so variable that recourse will have to be made to even more refined methods before a satisfactory species concept will be obtained.  It is unlikely that “bulk-ratio” will help solve any problems at species level, but there is no doubt that it can contribute to deciding limits of sections, subgenera and even genera. In the case of the two very closely related species H. maughanii and H. truncata, it would be very interesting to know why the leaves of the former species “spiral” and why in H. truncata they remain distichous.

 

Diagram 1. Leaf arrangement in Haworthia limifolia var. ubomboensis showing the two primary counter spirals.

Diagram 1. Leaf arrangement in Haworthia limifolia var. ubomboensis showing the two primary counter spirals.

Diagram 2. Representation of leaves diverging at an angle of 135° in which 8 leaf tiers are vertical and a 4° increase or decrease in leaf divergence to show the appearance of 5 and 3 parastichies respectively.

Diagram 2. Representation of leaves diverging at an angle of 135° in which 8 leaf tiers are vertical and a 4° increase or decrease in leaf divergence to show the appearance of 5 and 3 parastichies respectively.

 

New Haworthia (1974)

M. B. BAYER
Karoo Botanic Garden, National Botanic Gardens of South Africa

Published in CACTUS & SUCCULENT JOURNAL (U.S.), Vol. XLVI, 1974

Fig. 1. Haworthia geraldii Scott.

‘Out of Africa always something new’ is an expression the reader may excusably believe no longer applicable in the case of Haworthia. However, in the last 8 years no fewer than seven new Hawrthia species have been described. Three of these are by Col. C. L. Scott, one by Dave Hardy and Mr. Obermeyer and three by the writer. Many species have been deleted in the past two years and many more are destined to a similar fate—but it is also likely that new species will still emerge.

The real problem in Haworthia has been and still is the question of deciding just what constitutes a species, as this concept is rather difficult to define even for the most general application. A species is obviously not one single plant, but an aggregate of individuals which look alike and comprising a population or series of populations adapted to, and propagating in particular habitats. A species should not be described without duly considering this. In Haworthia one cannot generalize too much about what a species is either, as in the three subgenera (and add Astroloba and Poellnitzia if some authorities exercise their will) one finds apparently quite different systems in operation. Peter Brandham of Kew has recently demonstrated that entire and even widely separated populations of H. reinwardtii may comprise or contain genetically identical plants. This shows this species does propagate vegetatively and a species concept here may be quite unfitted for other species such as H. lockwoodii which do not propagate vegetatively in nature. In many cases the writer has found odd populations which are each quite distinctive and yet which must be outliers of more widely distributed and commoner species. If these are all to have names, taxonomy in the group may become quite unmanageable. It thus seems far wiser to adopt a rather broad species concept and rather include such populations under their apparent points of origin—if it is possible to do this.

H. geraldii Scott was described from the Riversdale area and is found just north and northeast of the town. The writer has only visited the northern locality where the plants do present a remarkable sight. Huge solid clusters of up to 1/2 meter or more in diameter containing 60 or more large rosettes slightly raised from the ground—beautifully colored greenish-yellow, with prominent face lines on the heavy thick leaves. About 200 meters to the west is a smaller population of another plant which appears to have some affinity to H. asperula (synonymous with H. schuldtiana?). This latter plant seems to breed true from field seed, which may seem rather odd when one considers how close it is to H. retusa and H. geraldii. A few kilometers east is the site of H. fouchei, and still further east in the Kafferkuilsriver one finds forms which lead on to H. longebracteata from the lower reaches of this river. The story does not end there, because westward from Stilbaai andsouth of Riversdale one finds populations still very near to H. longebracteata, until at the Duiwenhoks river at Heidelberg one comes to the source of H. nitidula. North of Heidelberg one finds a most classic example of ecotypic transformation in Haworthia. In the sandstone formations are typical H. laetivirens, in theshale a little to the south, the plants are larger and unspined until in the conglomerate at Heidelberg there is a motley complex of plants tending to H. nitidula (and hybrids with H. floribunda!). It is certain that all these populations must be regarded as components ofone species and that names such as H. fouchei, H. longebracteata, H. nitidula and also H.geraldii cannot rationally be maintained. Species such as H. turgida, H. dekenahi and H. caespitosa may also yet be excised. However, this is an extraordinarily difficult complex and good facts are really needed on which to base sound argument.

Fig. 2. Haworthia baylissii Scott.

H. springbokvlaktensis Scott is unquestionably a good species. Known for many years and recognized as H. mutica by collectors such as Major F. R. Long, W. E. Armstrong and other enthusiasts of the pre-war period, Col. Scott has correctly separated this species at Springbokvlakte. Growing together with Lithops terricolor in the typical sandy Karoid area east of Steytlerville, it is a most striking plant. The very rounded leaf tips and thumblike leaves, the purplish, translucent face area and darker face-lines make this a most attractive plant. It does not seem to be very plentiful and is seldom proliferous. More than one locality is known and evidence suggests that it is to some degree intergraded with the H. emelyae complex around Oudtshoorn. At Uniondale one finds plants which also indicate affinity with H. comptonii which in any case may best be regarded as a near ally of H. emelyae. H. mutica is now well-known to occur in the Bredasdorp/Caledon area (H. otzenii is synonymous here)—inclined to a purplish hue with unpointed leaves, it does extend eastward toward the notorious Riversdale area. It is very difficult to convincingly separate H. mutica from H. retusa and even from H. pygmaea at Mossel Bay.

H. baylissii Scott is from Oudekraal in the Somerset East district. This species has not been seen by the writer in the field and with two very disparate collections from that locality as well as deviations from the description, doubts as to its validity must exist. A collection at Kirstenbosch apparently received from Col. Bayliss (the collector of the species), is clearly H. angustifolia but with shorter, thicker leaves than normally encountered in that species. The locality is a little far west for H. angustifolia (not to be confused with H. monticola from the southern Karoo!) but the plants do also have the silver flecks as in co-types of H. baylissii, also in cultivation at Kirstenbosch. The main distinction of H. baylissii was said to be the recurving leaves, but this is not a stable character and none of the plants in cultivation either at Kirstenbosch or the Karoo Garden have this character. Why this species should have been placed in the section Muticae really serves only to underscore how abysmally weak the sections actually are. This section was originally created by Berger for H. reticulata, and eventually contained ‘H. hurlingii, ‘H. haageana’, ‘ H . intermedia* (all synonymous now) as well as a few other species including H. caespitosa. H. baylissii has quite patently no close affinity, difficult and obscure as Haworthia taxonomy may seem to be, with any of these species and until better understood should be considered close to H. angustifolia, but not necessarily to all species in the section Loratae.

Fig. 3. Haworthia springbokvlakensis Scott.
Fig. 4. Haworthia koelmanniorum Obermeyer & Hardy

H. koelmanniorum Obermeyer and Hardy was described from Groblersdal in the eastern Transvaal and this is far to the northwest of the nearest species, H. limifolia. The differences by which it was first separated from that species are quite invalid. As far as suckering is concerned, the different forms of H. limifolia do not all sucker freely, if at all; H. limifolia does not have a significantly different base to the rosettes, and if it did, would probably require separation at generic level! The tubercles on the leaves of H. limifolia vary enormously over the distribution range—from colorless, wavy, undulated ridges, to prominent white bars—from small, concolorous tubercles to large, raised pustules. The difference in phyllotaxis is also fallacious, as any admirer of the arrangement of spines on cacti will be quick to grasp. A l l Haworthia have their leaves spirally arranged and H. limifolia together with H. tesselata are rather exceptional in that the angle of leaf divergence is rather high, in the vicinity of 160°. This means that the two primary counter spirals are more readily apparent than the three secondary spirals. When grown together with many other collections of H. limifolia, the writer can see no exceptional reason for separating H. koelmanniorum from that species, other than the color being a deeper, translucent gray-green and the leaves bluntly tapering. The flower in H. limifolia is rather variable and there is no evidence here to suggest the H. koelmanniorum is distinct. Floral characters in the whole subgenus Hexangulares are, however, rather much of a muchness and not very helpful. H. tuberculata, together with H. starkiana, does have unique floral characters and to suggest the H. koelmanniorum has an affinity here is to do justice to neither species and offend the small differences which are of taxonomic value in the genus. Geographically speaking, the species is of note but it is not correct to talk of ‘outliers (of the genus) extending to Zululand, Swaziland and southeastern Transvaal*. It must be obvious from the above that probably only one species, H. limifolia, is involved, but perhaps sufficiently differentiated for local populations to be recognized at subspecies level.

H. pubescens Bayer is, with the next two species, a ‘creation’ of the present writer—and perhaps enough said! There is no doubt that this species has an affinity with the very difficult and variable H. schuldtiana complex. However, it is equally allied to H. herbacea.

Important distinctions include both vegetative and floral characters, flowering times, locality and ecological associations—and the author is not concerned with single plant characters or collections. H. pubescens comes from a very dry area south of Worcester and is hard to grow, requiring strictly winter watering and no direct sunshine. A well-grown plant is a pleasure to behold—the whitish pubescens on the dark green background give the incurved, abruptly pointed leaves a velvety appearance.

Fig. 5. Haworthia pubescens Bayer.

H. pulchella Bayer, nom. nov. in manuscript, can also be put in the gem category. The small, sparkling spined, emerald ball is the real jewel of the Karoo garden collection. First known to the writer through its discovery by the late Mr. Roy Littlewood and the recollected by Mr. F. J. Stayner, this species is from the very dry, desolate hills of the Touws River area. Its affinities are doubtful and the flower is as ordinary as that of an haworthia can be. Associated species do not give any leads either and the nearest species geographically speaking are H. setata and H. tessellata. Much further away are H. wittebergensis, H. lockwoodii and H. margaritifera. If the writer was forced to select a near ally, it would be H. monticola on the basis of floral similarity.

Fig. 6. Haworthia pulchella Bayer, Touws River.


H. serrata Bayer is no less contentious than H. pubescens. Occurring at several localities within a relatively small area, this species is one of the affiliates of the Heidelberg complex. In some forms the leaves are incurved, suggesting a robust plainly marked specimen of H. herbacea, while in others the leaves recurve as in H. heidelbergensis. The flower is characteristically rather bright green in the veins and does not have the closely plicate tips of the upper, outer tepals as does its expected relatives. That many leaves, among other considerations, remove it from H. retusa, and it must have close ties with H. rossouwii at Bredasdorp. H. serrata demands recognition, but how best to express its distinctiveness in among several almost unique populations in that area still eludes.

In concluding it may not be necessary to say that taxonomy in Haworthia has passed beyond cursory examination of the simple, external structure of the plants. What is really needed is some good morphological study aimed at analyzing characters which might be of better value in separating and circumscribing the species. Nevertheless, some kind of structure is necessary even to base such a study on, and any contribution must be gratefully welcomed.

Fig. 7. Haworthia serrata Bayer.

Name Changes in Haworthia Concerning H. Obtusa Haw. and H. Pilifera Bak.

M. B. B A Y E R & J. W. P I L B E A M

  1. National Botanic Gardens of South Africa, Karoo Garden, Worcester.
  2. Orppington, Kents, England.

Published in CACTUS & SUCCULENT JOURNAL (U.S.), Vol. X L V I , 1974

Fig. 1. Water-color by Thomas Duncanson in Kew Library of Haworthia ‘obtusa’ Haw. This
is the water-color reproduced by Uitewaal in 1948 in Succulenta on which his name-changes
were based.

ABSTRACT: The application of the names H. obtusa Haw., H. pilifera Bale., H. stayneri von Poelln. and H. gordoniana von Poelln. are discussed. It is concluded that Uitewaal (1948) erred in associating H. obtusa and H. pilifera, and that ‘H. obtusa’ is nothing more than a form of H. cymbiformis (Haw.) Duval, perhaps warranting varietal status. The name H. pilifera is thus reinstated for the species centered around the Kingwilliamstown area. Morphological differences are noted in the species H. stayneri and H. gordoniana which suggest, for the present at least, that these names should be retained for species complexes yet to be fully investigated; it may prove that these are merely smaller forms of H. pilifera occurring from SW Grahamstown to Port Elizabeth and on to Humansdorp.

INTRODUCTION: The purpose of this paper is to examine the application of the name H. obtusa Haw. by Uitewaal (1948). Uitewaal bases his argument on a water-color plate in the Kew Library purported to be H. obtusa (fig. 1), but which does not agree with Haworth’s description of the species. He concludes that H. pilifera Bak. must be synonymous and relegates this species to varietal rank under H. obtusa with a new description of the species. Haworth, however, clearly related his species to H. cymbiformis, and in view of problems involved in the application of these names to field populations, it is necessary to question Uitewaal’s conclusions.

INVESTIGATION: Both H. cymbiformis and H. pilifera are widespread and common species in the East Cape. Apart from gross morphological differences, these species differ basically in their habitat preferences, and may be found growing in close association. H. cymbiformis is essentially a riverine species growing on steep rock faces along streams and rivers, and mostly among valley bush vegetation associated with these conditions. It is characteristically a bright green species forming dense mats with compacted roots confined to shallow crevices and cracks of the comparatively soilless habitats. It may become dull green to yellowish-brown or red in its different forms and under different growing conditions. H. pilifera on the other hand, while also found along streams and rivers, occurs in grassland vegetation in sparsely covered rocky situations and usually shallow soils. It is characteristically gray-green in color with pink to purplish hues – never acquiring the brilliant green of H. cymbiformis or becoming dirty brown as Haworth’s description of H. obtusa. It may also form dense mats but with thick fleshy and spreading roots, while the leaf surfaces are level with the soil surface in exposed situations. There should, therefore, be no question of confusing these two species. A form of H. cymbiformis which agrees with the Kew illustration is recorded by G.G. Smith (fig. 2), and this was found growing in a typical population of the species. Other forms have frequently been seen by the writers in cultivation which, by reason of their similarity of form, coloring, habit and floral characters, suggest a similar origin.

Fig. 2. Haworthia cymbiformis Haw. G. G. Smith’s no. 3389a – a form from Ft. Jackson, Nahoon River


One such plant has been cultivated at the Karoo Garden in shady conditions and then transferred to brighter light for five months (fig. 3) to see how it would compare with the various forms of H. pilifera under similar conditions, and with the Kew illustration. The result confirms that a plant occurs within the writers’ concept of the H. cymbiformis complex which agrees with the Kew illustration but which cannot be associated with H. pilifera. The test plant became brilliantly green under the brighter light conditions, the leaves were shorter but retaining their turgid spreading attitude, neither truncating nor developing necrotic tips. The plant remained above the soil surface and did not recede as H. pilifera does under exposed conditions. Furthermore plants grown in association in cultivation for several years of a plant similar to figure 3 and varieties of H. cymbiformis and H. pilifera, clearly exhibit that the former is in character allied to H. cymbiformis and not H. pilifera.

Fig. 3. Haworthia ‘obtusa. The test plant transferred from shade to sunlight. Origin unfortunately uncertain but alike in every respect.

At the time Uitewaal submerged H. pilifera under H. obtusa, G.G. Smith wrote to J.T. Bates in England that “Mr. Uitewaal and one or two others have recently sunk several of the old well-known names, but I have not accepted all the changes … The H. obtusa, taking the place of H. pilifera, is H. cymbiformis var. obtusa … H. pilifera has never been found on a krantz (rock-face), whereas H. cymbiformis and its varieties are only found on krantzes, and I have plants from a couple of krantzes which are varieties of H. cymbiformis and in a photograph look more like H. pilifera than H. obtusa does … what is more he (Uitewaal) makes up a description from the painting!”.

J.R. Brown in his ‘Notes on Haworthias’ in the American Society’s journal wrote of H. obtusa: “This Haworthia has long been given the name of Haworthia cymbiformis var. obtusa (Haw.) Baker, but the numerous plants under this name which I have seen have only been cultural variations of Haw. cymbiformis Haw.”

The most extraordinary part of Uitewaal’s proposal is that he regards the original description of H. obtusa by Ha worth as “defective and misleading” and, as Smith points out, then proceeds to describe the plant from the painting. The painting itself is by an artist, Thomas Duncanson employed at Kew contemporary with Haworth, and it is more probable that this diverges from the plant it is intended to portray than Haworth’s written description. Anyone who knows Haworthia well (despite Uitewaal using this same claim to support his own contention) must in looking at the Kew watercolor bear Haworth’s description in mind and relate H. obtusa to H. cymbiformis.

Haworth’s description reads as follows: — obtusa H. (small blunt hollow-leaved) foliis ovatis concavis luridis obtusis cum mucronulo, apicam versus pellucentibus, lineis saturatioribus.
Habitat C.B.S. G.H. 4
Obs. H. concava Nob.* in Revis.Succ. proxima, at subduplo minor, colore adhuc lurida, et minus virente glaucove quam in ilia, foliis apice crassioribus obtusioribus magis pellucentibusnmagisque striatis. Flores ut in affinibus.
(Haworth-Phil. Mag. 1825)

(Translated: —
obtusa H . (small blunt hollow-leaved) leaves ovate and concave dingy yellowish-brown obtuse with sharp point, pellucid towards the apex, filled with lines.
Habitat C.B.S. G.H.4
Obs. near to H. concava Nob.* in Revis.Succ. but nearly half as small, color until now dingy yellowish-brown, and less glaucous green, leaves thicker and more obtuse, more pellucid and lined. Flowers the same).

* FOOTNOTE: H. concava was subsequently declared synonymous with H. cymbiformis.

Fig. 4. Haworthia vittata Bak. The illustration accompanying Baker’s original description dated March 1871.
Fig. 5. Haworthia cooperi Bak. The illustration accompanying Baker’s original description dated September 1870.


Of particular note are Haworth’s comments on the color, and on the flowers. The flower of H. cymbiformis is a clear white and generally borne on a short, slender peduncle, and Haworth does state that the flower of H. obtusa is the same. In H. pilifera the flower is off-white and borne on a generally stout peduncle. What is difficult to concede, is that Haworth never received specimens of H. pilifera and that it was left to Baker to first describe the species as well as the near relatives H. vittata (fig. 4 ) , H. cooperi (fig. 5) and H. columnaris. These latter species must almost certainly be included in the synonymy of H. pilifera, although the two first named of these may perhaps represent introgression of H. pilifera toward H. blackbeardiana von Poelln. Field observation indicates that there is no good evidence to support varieties (in the botanical sense of sub-species), as variation across the distribution range of H. pilifera is both large and evidently continuous. Observations on the many collections of this species yield some interesting observations. Some variants are very bristly with markedly and acutely pyramidal leaf-tips, and others have rounded and minutely mucronate leaf-tips. Of particular note was H. stayneri from type locality. This species remained small but the leaftips truncated with the end-bristle curving in, and together with the veins of the back upper leaf surfaces, dying to form a whitish necrotic network across the end-area. The differences between sun and shade forms of H. stayneri are shown in figure 6. Variations within a collection of this species from type locality invalidate the variety H. stayneri var. salina (syn. H. pilifera var. salina) von Poelln. H. gordoniana grown under exactly the same conditions became deeply submerged in the ground but the leaves remained erect and narrowly pointed (fig. 7), and also did not assume the deeper purplish to gray-green hues of H. pilifera or H. stayneri.

Fig. 6. Haworthia stayneri von Poelln. Sun and shade grown forms.
Fig. 7. Left: Haworthia gordoniana von Poelln. Sun grown plant. Right: Haworthia stayneri von Poelln. Shade grown plant.

CONCLUSIONS: No progress will be made towards a stable and rational nomenclature in Haworthia until names are firmly attached to field populations. It is clear from the above observations that Uitewaal was wrong in regarding H. obtusa to be “unmistakably” associated with H. pilifera and also wrong in amending Haworth’s original description. In view of the confusion now in correctly applying Haworth’s name, and assuming that the illustration at Kew is in fact Haworth’s species, it is proposed to recognize the name H. obtusa as applying to the H. cymbiformis complex, reducing it to synonomy with that species. At the same time it is recognized that the state of naming in the H. cymbiformis complex leaves much to be desired, and it is hoped that further investigation will rationalize this species. The name H. pilifera is retained for the complex found in the Kingwilliamstown, Kei Road and Komgha areas – also requiring further investigation in regard to variation and distribution. This species is more widely distributed than has hitherto been indicated, and is found eastward to Idutywa, north-westward to Bedford, Cradock and westward to Grahams town. It is typified by the illustration accompanying Baker’s description (fig. 8) in Saunders Refugium Botanicum. It is fairly certain that the ‘species’ H. vittata Bak. and H. cooperi Bak. found in the Cathcart area, are northern ecotypes of H. pilifera and will eventually be regarded as synonymous of H. pilifera*.

Fig. 8. Haworthia pilifera Bak. The illustration accompanying Baker’s original description dated September 1870.

It appears to be a practical necessity at this stage to recognize H. stayneri and H. gordoniana as discrete species in consideration of their distribution and the morphological differences recorded here. Both species require further investigation — H. stayneri particularly in relation to the distribution of H. pilifera in the Grahamstown, Alicedale and Bedford areas, and H. gordoniana in relation to the vast complex of the Gamtoos river valley, Humansdorp.

The name H. columnaris Bak. is discarded as being probably a synonym of H. pilifera: described by Baker in 1889 the plant was originally received at Kew from an Exeter nursery, and can be regarded as a variant of H. pilifera.

H. dielsiana von Poelln. and forma acuminata von Poelln. are also discarded as local variants of H. pilifera.

H. obtusa var. pilifera forma truncata Jacobsen is discarded as a misidentification for H. umbraticola von Poelln., cf. original descriptions and photographs of both.

In the context of this paper the following taxa are upheld: —
H. pilifera Bak. (formerly H. obtusa var. pilifera (Bak.) Uitew.)
H. cymbiformis Haw.
H. stayneri von Poelln. (formerly H. obtusa var. stayneri (von Poelln.) Uitew.)
H. gordoniana von Poelln. (formerly H. obtusa var. gordoniana (von Poelln.) Uitew.)

Rejected are: —
H. columnaris Bak. (subsequently H. obtusa var. columnaris (Bak.) Uitew.)
H. dielsiana von Poelln. (subsequently H. obtusa var. dielsiana (von Poelln.) Uitew.)
H. stayneri var. salina von Poelln. (subsequentlyH. obtusa var. salina (von Poelln.) Uitew.)
H. obtusa Haw.

Questionable are: —
H. vittata Bak.
H. cooperi Bak.

It is a pity that it has taken so long to refute what was plainly a tenuously-based decision, but it is confidently expected that these new proposals will facilitate investigation and communication regarding the plants concerned and their respective origins.

REFERENCES
Collection of Haworthia illustrations in the Library of the Royal Botanic Gardens, Kew, England (to which the authors are grateful for permission to reproduce the painting)

Succulenta i9:101 (1937); 30:49 (1948) – Uitewaal

Cactus & Succulent Society of America Journal 10:57, 88 (1938); 36:75 (1964); 37:115 (1965) – J. R. Brown

Philosophical Magazine 1825:282—Haworth Journal of Botany 37:45 (1889)-Baker Fedde’s Repertorium 28:103 (1930); 42:269 (1937); 44:235 (1938); 49:23 (1940) – von Poellnitz

Saunders Refugium Botanicum 4:t. 233, t. 234 (1870), t. 263 (1871) – Baker

Desert Plant Life 15:124 (1943) – J. R. Brown National Cactus & Succulent Society Journal 10: 81 (1955)-Jacobsen

*FOOTNOTE: It should be particularly noted here that if such a decision is reached, then the name H. cooperi Bak. will have page priority and will need to be adopted for the whole species complex.

Haworthias – small relatives of Aloe (1974)

Printed in Excelsa 4:17 (1974)

Introduction

There are few succulent collections which do not include haworthias, although these small and insignificantly flowered plants are not good garden subjects.  Their size, and shade and shelter requirements make them better suited to intensive cultivation in raised containers under shelter.  Very popular with collectors especially prior to World War II, the decline in popularity can be attributed to various factors.  Although the genus is credited with some 160 species and more than 250 varieties, it is highly unlikely that more than 90 species and perhaps 10 sub-species would survive a critical revision.  Many species have been eliminated in recent years, but there are still many maintained only by the mystery of their origin.  Hybrids and ill-defined or inadequate species account for many superfluous names.  The result is an artificial pseudo-scientific system of nomenclature in which the classic binomial system is prostituted for a series of horticultural cultivars.

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Haworthia Duval: Section Retusae fide Scott — Additional Comment (1974)

Printed in Aloe 12:89 (1974).
M.B Bayer, Karoo Botanic Garden, Worcester.

The ‘retuse’ haworthias are among the most fascinating of the genus and therefore Colonel Scott’s recent revision is of particular interest.  This work…‘A revision of the genus Haworthia, Section Retusae” was published in ALOE, Dec.1973 and forms a new taxonomic record of the species involved.  The object of the present paper is to examine the validity of this record particularly in the light of past history of Haworthia.  A considerable literature on Haworthia is now available much of which points to the problems likely to be encountered in the group. Much of it also points to the consequences of inadequate species concepts for the group.

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The ‘Retuse’ Haworthias (1975)

Printed in Excelsa 5:83 (1975).
(This article was subsequent to the revision of the Retusae by C.L.Scott).

The 162 named species in the genus Haworthia Duval have been split into 20 sections of which Retusae Haworth is one.  The clearest and most obvious subdivision in Haworthia is into three subgenera which are based on both floral and vegetative characters.  The Retusae fall into the subgenus Haworthia which contains the soft- leaved stemless species in which the three outer petals of the flowers completely enclose the inner petals.  Division within this subgenus is the most difficult of the three and thus the composition of the section Retusae is understandably problematic.  The type species of the section is H. retusa (L.) Haw., so named on account of the fat, bent, thumblike leaves.  In theory this type of leaf should characterise all the other species in the section.  However, in the field it soon becomes apparent that apart from the difficulty in recognising and identifying “species” related to H. retusa, some of these related elements do not have retused leaves.  What then is the composition of the section Retusae and how can the individual species be recognised?  So far the only really satisfactory criterion we have is the geographic distribution and relationship of a large series of rather localised populations.  The individual plants in each of these populations differ to a greater or lesser degree from each other, and in similar manner, the populations differ from each other.  Thus we have variability within and between populations.  The composition of the Retusae is based here on visual assessment of the discontinuities of this variability, on geographic distribution, and on habitat.

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Haworthia mirabilis Haworth. (1977)

Printed in Excelsa 7::37 (1977).
M.B.Bayer

Haworthia mirabilis was described by Haworth in 1804 from plants said to have been brought to England by the collector Francis Masson.  It could thus have originated from practically anywhere in the southern and south-western Cape.  Haworth referred to this species as the ‘rough cushion cushion’, and it was characterised by having retuse-deltoid leaves with ciliate-spinose margins and keels, the leaves being smooth on the face and the back surfaces almost tubercled and indistinctly reticulate.  There is no extant type specimen and only the brief original description, and illustrations in Curtis’ Botanical Magazine (t 1354, 1811) and in Salm-Dyck’s Aloe Monograph (s9, t 1, 1836-49) serve to identify and typify the species.

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Natural Variation and Species Delimitation in Haworthia Duval. – Part 4. HAWORTHIA EMELYAE von Poelln. and a new variety. (1979)

Printed in National Cactus and Succulent Journal, 34:28 (1979).
Part 4: HAWORTHIA EMELYAE von Poelln.and a new variety.
M. B. Bayer, National Botanic Gardens of South Africa, Karoo Gardens, Worcester.

Abstract:
The retention of the name H. emelyae v. Poelln. over H. picta v. Poelln. and H. correcta v. Poelln. is discussed.  There is also a discussion of the relationship of H. emelyae to H. comptoniana Smith. to H. springbokvlakensis Scott and to H. magnifica var. major (Smith) Bayer.  A new variety, H. emelyae var. multifolia is described.

Introduction:
Haworthia emelyae was described by von Poellnitz in 1937 and named in honour of Mrs Emely Ferguson whom von Poellnitz presumed to have been the collector.  Von Poellnitz related his new species to H. willowmorensis v. Poelln., to H. ryderiana v. Poelin. and to H. whitesloaneana V. Poelln..  None of these names is currently upheld (see Haworthia Handbook. Bayer, 1976) and it would be extremely difficult to form a picture of H. emelyae from any vision conjured up from the little tangible evidence associated with them.  Similarly the variety H. emelyae var. beukmannii v. Poelln. is known to be a variant of H. mirabilis Haw. (see Bayer, Excelsa 7: 37, 1977) and offers no solution to the problem.  There are three photographs supposedly of H. emelyae in the H. G. Fourcade photographic record of Major F. R. Long’s collection.  This record was compiled in 1940 and one would have expected less discrepancy at this distance in time than the three photographs actually project.  One photograph is of a plant sent in by a collector and recorded…”from the Gamka river, Calitzdorp”.  The plant is obviously H. turgida and comparable with the forms of that species from along the lower tributaries of the Gamka River (which actually becomes the Gouritz River after its confluence with the Olifants River in the Rooiberge to the north-east of Vanwyksdorp).  The second photograph is of a plant in the collection of W. R. van Ryneveld which is also clearly H. turgida comparable with the Lower Gouritz and Mossel Bay forms.  The third photograph is of a plant recorded as from Mrs E. Ferguson herself and this is unmistakably H. reticulata Haw.

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A Story of Haworthia Nitidula v. Poelln. (= H. mirabilis Haw.) (1980)

Previously published Cact S.Jl 52.1 1980
M. B. Bayer, Karoo Botanic Garden, National Botanic Gardens of South Africa

Haworthia nitidula was described by von Poellnitz in Desert Plant Life (11:192, 1939) from plants collected by Major H. Venter.  Venter was very generous with his localities and like most of his others, this no. 15 was also simply cited… “in the environs of Worcester, Swellendam, Caledon and Bredasdorp”.  This is an ideal example for demonstrating the problems of identification of haworthias and especially in the section Retusae Haworth.  J.R.Brown illustrated H. nitidula in the Cactus and Succulent Journal (18:89, 1946) but apart from this and the original illustration accompanying the description, the plant has not figured in the succulent literature.  In G.G.Smith’s records, the species and nine varieties are distinguished.  The interesting thing is that these varieties are drawn from three geographically separated species.  The object of this article is to present Smith’s photographs and notes of his “varieties” and discuss their actual position as they relate to distribution.

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Looking for Haworthias (1980)

Printed in Calandrimia, Succulent Publication, South Australia. :57 (1980).
M.B. Bayer, Worcester, South Africa

The attraction of Haworthias is their interesting diversity of leaf arrangement and form, as their flowers certainly do not attract attention.  My own interest in these plants owes itself certainly to my introduction to a plant then known as Haworthia chalwinii.  This is now know to be a variation of H coarctata in which the leaves are shorter and more closely adpressed to the stem than is normal.  Even now I am still impressed by the closely-incurved, tubercled leaves packed tightly above one another on a stem which may he up to 20 cm long.  Although I was scarcely 10 years old then, the memory of dense mats of H. cymbiformis on a riverine rock-face in the eastern Cape is still a strong one, but interest remained dominant until nearly twelve years later.  My father was stationed in the Natal Midlands and an uncle, who was a Health Inspector in the malaria areas of northern Natal, brought in an Haworthia from those parts.  J.R. Brown’s book…”Succulents for the Amateur” was one of my favourite books and by that stage would fall open at the section on Haworthias.  The picture of H. bolusii most impressed me and I felt that I knew enough then to recognise these plants from Natal as something new.  They seemed to me quite unlike H. limifolia which 1 knew from illustration, and I thought they should be described as a new species particularly to record the occurrence of the species in Natal.  Fortunately Dr. R.A. Dyer, Chief of the National Herbarium in Pretoria, persuaded me to be more moderate and the plant was eventually described as H. limifolia var gigantea.  Dr. Dyer also suggested that it would be wise to investigate the species in the field and so launched a 5,000 km wild-goose chase across northern Natal, Zululand and Swaziland.  The only direct success my companion and I had was in meeting Captain D.R. Keith at Stegi on the eastern border of Swaziland.  He directed us to the bottom of the Umbuluzi Valley where we found H. limifolia growing in vast quantity on the shaded dry forest floor On reflection I wonder why he did not direct us to his original farm Ravelston where the vars keithii and ubomboensis were found.   Although we found no other plants, we did find evidence of plants from as far afield as Paulpietersburg. Barberton, Gollell, Mozaan, Hluhluwe and even as far south as Stanger.  The plant is used by native witch-doctors and herbalists as a remedy for a variety of ailments and one recorded use is for the plants to be placed on the tops of the huts as a lightning deterrent.  Our collecting trip was thus highlighted by endless cross-examination of the rural blacks crying to locate where the plants could be found.  Neither of us had more than a smattering of the Zulu language and this was probably our main stumbling block to success.  On one occasion we were excitedly directed towards an unlikely looking hillside to find a police contingent waiting for us on our return to the vehicle.  Our ‘guide’ had taken us for communist agitators.  Another highlight was being marooned in the Umfolozi Game Reserve by flooded rivers.  Taking advantage of the forced respite, we thought we would explore the Reserve itself, famous as the then last resort of the white rhinoceros.  Our intrepid guide directed us off on a side road in search of the hotter-tempered black rhinoceros and we were soon axle-deep in thick black sticky mud.  The guide was most reluctant to get out of the car and help dig, push and curse while we tried to extract it from the mire.

In retrospect it is a pity that we did not make a more concerted effort to see H. limifolia in the field.  It is clearly a widespread species but in localised and isolated populations and subject to indiscriminate collecting.  I would particularly have liked to have seen the variety ubomboensis in the field, although each locality seems to produce a distinctive form.  After our exhaustive trip, the distant Cape became the obvious place for Haworthias.  My job held no prospects for getting there and a disaster to my collection in which all my labels were removed, persuaded me to abandon any further attempt at getting to know the genus better.  Although I had acquired a considerable number of plants, very few of them were authentic field collected plants and none were authoritatively named.  The few authentic specimens did not take readily to cultivation and I decided that, rather than collect for the compost heap, I would stop collecting.  Soon after this I moved to Johannesburg to be lost in a concrete jungle for four years until I was transferred to Cape Town.  At first I was reluctant to start collecting plants again and I confined myself to finding and seeing Haworthias in unfenced likely looking hillsides during travels through the karoid areas of the south-west Cape.  A visit to Kirstenbosch introduced me to the Fourcade/Long photographs, but more importantly to G.G. Smith’s collection and record.  G.G. Smith’s published work may not be of very much value, but the value of his herbarium material is inestimable.  The average collector (and it appears so for some would-be taxonomists too) can have no concept of the relationship of a herbarium specimen to a plant name or of the importance of proper herbarium record as a permanent, reliable record.

Among the first Haworthias I saw while in the Cape were plants of H. chloracantha near Great Brak. They were growing on a hot north-western slope with the tips of the leaves at ground level and betrayed only by a few old dry flower stalks that caught my eye (I cannot account for the change at this locality which is now heavily vegetated and quite unsuited to the haworthia).  This was followed by finding H. mirabilis ssp. badia at Napier growing in among small multi-coloured pebbles.  The leaves were the identical colour shades of yellow, white and orange as the pebbles and the plants were as difficult to see as any Lithops.  At one point I called my wife to come and locate three plants in a 15 cm (6”) square plot – she missed them, but pointed out two others which I hadn’t seen.  In those days we were still inexperienced and it was often a battle to find the plants.  I have since been back to the site where I first had the thrill and excitement of finding H. magnifica, to find that there were considerably more plants than I could have imagined on my first visit.

Several years earlier I had been corresponding with Roy Littlewood who was Horticulturist at the Karoo Botanic Garden.  Passing through Worcester one day I thought I would take the opportunity of ‘looking him up’ and meeting him personally.  It was a hot, dry day in February and I was singularly unimpressed with the Garden which had a country-wide reputation for the spring-flower display.  The Curator was Mr. F.J. Stayner who told me that Roy had died the previous year as the result of a heart-attack while collecting butterflies in the mountains nearby.  At that time Roy’s post was filled, but six months later was again vacant.  This time the old personal conflict between trying to forge a career and doing something which I was really interested in finally resolved itself.  I presented myself at Kirstenbosch and, in the absence of any other applicants, was lucky enough to be appointed to the post ‘Assistant to the Curator’ at the Karoo Garden.  Mr. Stayner was very good to me and I was allowed to devote my time to replanting and re-organising the extensive Haworthia collection which included a great many of Smith’s original plants.  The Curator of the Compton Herbarium at Kirstenbosch was also good enough to let me have all Smith’s papers to work on at Worcester.  It was immediately obvious that very little was known about the Haworthias in the Worcester/Robertson area and that all the available names bore very little relationship to the natural association of the plant populations in the area.  For one species growing indigenously in the garden and common throughout the area, there was no positive identification and about seven names to choose from.  Then there was Haworthia magaritifera (pumila) and all its variants as well as names such as H. semimargaritfera and H. papillosa to choose from too.  It was not surprising that as a collector in Natal I was being confused by the available literature.  A species such as H. reticulata had never been validly recorded from the field since it was described by Haworth in 1804 and yet here it was growing commonly in the area.  The problems involved in trying to ‘tie a name down’ for the species indigenous to the garden, now H. herbacea, proved that the identification by and from simple verbal description was going to be an insuperably difficult job.  Certainly comparison and separation of closely related species or populations on this basis would be virtually impossible, and this is a point which the collector should not forget.  There are many facets of the Haworthia charade which need to be appreciated by enthusiasts.  The first of these is that interest in the plants is associated with rivalry and antagonism.  The exchanges between Smith, Resende and Uitewaal were quite unnecessary and many other authors contributed to confusion and misunderstanding in the genus.  One common error which impressed me was the identification and matching of plants from illustrations or photographs.  So many times Smith, Long, Brown, or ‘A. N. Other’, would take one picture and match it with a comment like…”agrees with…” and so often this would be quite wrong.  Among the most blatant errors of this kind was the confusion of H. limifolia from northern Natal identified as H. margaritifera var. granata sub-var. polyphylla.  Many plants were described as varieties and forms of species which themselves had not been rediscovered or positively identified.  Plants from single populations were frequently classified down to varieties and sub-varieties of different species. In some cases species were being incorrectly identified at the level of sub-genus, and, for example, forms of H. fasciata were being confused with H. margaritifera.  Even Aloe aristata collected in the mountains of Natal had been collected and taken for an Haworthia and an herbarium specimen still bears the. manuscript name H. natalensis sp. nov.  It is more than likely that H. ferox was actually Aloe humilis.

When I first obtained Smith’s notes they included very few indications of how he intended to finally treat the genus.  There were of course all his published species and varieties and his final article “Views on the naming of Haworthias”.  In 1976 Kirstenbosch acquired many more papers from the estate of G.G. Smith through the kind agency of Dr. M. Courtenay-Latimer who had done so much of Smith’s paper work.  These papers contain Smith’s assessment of his collection and it is interesting to note just what he had in mind.  Firstly it is clear that he had no species concept whatever and that he had an immense hoard of new species and varieties in mind.  In the ‘retusae’ he had nine varieties of H. nitidula (which is a synonym of H. mirabilis) drawn from three different species.  He had designated two varieties of H. pygmaea, fifteen varieties of H. retusa, a variety of H. rossouwii (H. mirabilis), three varieties of H. dekenahii, three completely new species and several sub-varieties.  In H. viscosa he had earmarked seven new species, and in H. reinwardtii he had a further four varieties for description.  No one should underestimate Smith’s observations and the detail with which he compared his plants.  Each description was preceded by a point-for-point check-list of characters and he insisted in growing all his plants for several years before coming to conclusions.  Smith had virtually set himself several life-times’ work to classify and describe each variant he encountered.  Unfortunately this kind of single-minded intensity still persists and there are still collectors following the same path, but with plants which do not even have the merit of field origin.  It is not in the least surprising to find that there was so much difference of opinion concerning identification.  For many names there was no type plant of any kind and it is really ridiculous to find controversy where neither party had any basis for argument.  Unless there is some reference point for a name and unless there is some appreciation of what a name actually stands for, argument as to identification is totally futile.  It is tragi-comic to find collectors who still insist on using the nomenclature abandoned by Smith and von Poellnitz.  In most cases this excludes about 95% of the natural populations and leaves the remaining 5% in a curious and impossible tangle.  It should be remembered that most plants now in cultivation, particularly overseas, probably are derived from plants propagated during the Triebner era or earlier.  These are mostly species which propagate vegetatively and are difficult to kill with kindness.  Possibly more than half the actual existing species are not even in general cultivation.

During my first three years at the Karoo Garden I spent much of my time following up G.G. Smith’s locality records.  One interesting trip involved following a diarised record of the collector Otzen through the south-western Cape.  Several localities no longer existed, but it was an impressionable experience to come again upon localities which he had visited 40 years before.  One of these involved the locality for H. otzenii (=H. mutica), and it was clear that the origin of this species had been confused.  I met many most interesting and helpful people figured in the records and literature such as Mr. A.J. Joubert, a schoolteacher now retired, at Ladismith; and Mr. J.J. Dekenah at Riversdale who must have been on nodding acquaintance with every Haworthia plant within a 50 km radius of the own.  I met Mrs. L. Lategan at Oudtshoorn to try to extract cite veiled mystery behind the name ‘H. smitii’, and Mrs. Baldii (nee Taute) who verified the locality for her mother’s find H. tauteae.  Mr. C.J. Payne still lives at McGregor and is a complete character in his own right.  He is a bachelor, the local church organist and the possessor of one of the greatest collections of South African sheet-music.  He has lived all his life in this remarkable backwoods town and still has a derelict collection of Aloes dating back from C.W. Reynolds’ pre-war collecting activities.

Having seen all the known species of Haworthia in the field, each name conjures up related memories.  The setting has varied from H. chlorocantha in the middle of the town of Mossel Bay (now a concrete jungle), or H. unicolor in the caravan park at Barrydale, to H. wittebergensis in the solitude and grandeur of the mountains.  H. marumiana was a complete mystery for many years until Bruce Bursey introduced me to Cameron McMaster at Cathcart.  Cameron showed me a plant which he had collected along a remote road south of Tarkastad in the northeastern Cape.  I arrived at the locality late at night and had to spend a wretchedly uncomfortable night contorted in the cab of the small truck I was driving.  However, I was rewarded by finding the plants the next morning and so could confirm that the species is in fact from the mountains of the Great Karoo and north-east Cape, and not the little Karoo as stated. H. lepida also gave a lot of trouble, although the locality was recorded fairly accurately by G.G. Smith.  We spent two days in the hot dry dusty Fish River valley scouring the steep brush-covered hillsides and had to conclude that the population no longer existed.  This was probably the only occasion on which I could not confirm one of Smith’s records and we had to content ourselves with a population a few miles further on.  However, Smith did make a serious error in the case of H. baccata.  He described this species without seeing it in the field and it is practically certain that it never was collected from Stutterheim as recorded.

I shall never forget the two weeks spent with Dan Timm in the Grahamstown area looking for H, coarctata and H. reinwardtii.  We particularly visited the farm Hopewell’, which was a Smith family farm, and where G.G. Smith had found H. musculina, H. fulva, H. greenii var. silvicola and also identified H. coarctata, H. chalwinii and H. reinwardtii.  After repeated visits and hours and hours of scrambling, stumbling and falling through dense thorny thicket we could only conclude that there was one species on the farm and not even as variable as all Smith’s identifications suggested.  It is the sort of place that Mr. J.W. Dodson, or the New South Wales Study Group would really appreciate.  We also looked for Smith’s varieties of H. angustifolia and it took considerable detective work and eventually pure luck to find the plants.  We found the variety paucifolia only by virtue of the fact that the plants were in flower, as otherwise they are completely hidden among dense thickets of grass-like Restio.

It was G.J. Payne who caused me the most collecting grief.  Late one afternoon following two very strenuous days in the undulating Robertson-Bonnievale area, I passed through McGregor and called in the see Mr. Payne.  He said that he had once collected an Haworthia at a place called ‘Die Galg’ in the nearby mountains, and we duly set off to look for it.  ‘Die Galg’ (in English ‘The gallows’) is a very impressive incomplete pass or cut, high up in .the Riviersonderend Mountains.  It is the start of a long, deep valley which runs southwards to Greyton and the Riviersonerend River about 25 km away.  During the War years, Italian prisoners had been put to work making a roadway through the valley, starting at Die Galg at the top.  It was an impossible task and the road was never remotely finished.  It petered out completely after about one kilometre, over a steep-sided valley with the deep gorge winding away in the distance to the south.  Mr. Payne said that he would stay and wait as he did not feel fit enough to accompany me and in any case the plants were not far and the place was easy to find.  Previous experience had shown tine and again that collectors (Payne included) had seldom ventured far from the beaten track and so despite my tiredness, I climbed down into the gorge.  After miles of rough, narrow, often indiscernible track I did eventually find the plants, but the light was already fading as I turned to go back.  I have seldom managed so good a night’s sleep in a room of a country hotel, above the pub on a Friday night.

Very long distances were usually involved in collecting trips but the most hazardous eventually turned out to be a local search.  Smith had an odd record of plants collected ‘at 4,000 feet, Audenberg Peak’.  The Karoo Garden is at 1,000 feet and thus the locality was somewhere high on a series of four tooth-like peaks a few miles north of the garden.  The original collector of Smith’s plants was Miss Elsie Esterhuyzen, an ageless, spry queen of the Western Cape mountains who is still associated with the Bolus herbarium at the University of Cape Town.  It took time, co-ordination and organisation to get a party together for the climb and it was a disappointment to wake up in the morning to rain and mist.  Undaunted, Elsie led us on what, with anybody else, would have been a completely foolhardy venture.  The climb was a very steep one and at times we could only guess where the almost vertical rock sheets ended in the swirling mist below.  In most places there was no track or path at all because even the local mountain club members very seldom ventured there.  However, Elsie led us unhesitatingly right to the plants – no mean achievement when one considers that she had been there once thirty-five years before.  It was a bit of an anti-climax to later find the same variant of H. herbacea (H. maculata) within fifty metres of the National Highway in the Hex River Pass at an altitude of 1,000 feet.  It is this kind of record which will eventually pave the way for a real understanding of the complexity in Haworthia.

After contemplating the difficulties of Haworthia taxonomy, I pushed the thought of a book completely into the background.  Although they have such fascinating forms they are almost devoid of characters by which they can be identified by eye.  The species are separated by nuances of shape and colour and often there are no clear boundaries within whole groups such as in the retusae.  The decision to produce a booklet was finally undertaken simply to record a workable assessment arrived at after considerable involvement with the group.  The original title of the booklet was “Haworthia – an Illustrated Check-list”’ and it is intended solely as a guide to the nomenclature and literature in the genus, and to streamline the nomenclature to a more relevant and workable one.  Names are not for collectors, but provide the basis on which information is collected and collated about our environment.  No matter how many books are written on Haworthia, however profusely illustrated, the collector will never at this point in time be able to identify all the plants he encounters with complete certainty.  He will have to concede that each species name covers a variable group of plants.  In some cases the species are not absolute and technically should perhaps not even be regarded as species.  John Pilbeam of England is presently completing a more comprehensive book on Haworthia and this will indeed give the collector something to which he may look forward.  Perhaps we can look forward to an era where a genuine concerted effort is made towards propagating and distributing those species which have so far been rare in cultivation.

Natural Variation and Species Delimitation in Haworthia Duval. – Part 5. HAWORTHIA ANGUSTIFOLIA Haworth. (1981)

Printed in National Cactus and Succulent Journal, 37:31(1981).
Part  5. HAWORTHIA ANGUSTIFOLIA Haworth.
M. B. Bayer, National Botanic Gardens of South Africa, Karoo Gardens, Worcester.

Haworthia angustifolia was described by Haworth in Philosophical Magazine in 1825 as follows:- “(slender leaved) leaves lorate attenuate, curved, widely recurved, wholly green, apex nearly keeled, keel armed with small closely spaced teeth from point of emergence.  Similar to H. chloracantha Haw., but smaller, leaves narrower, more recurved and longer, 3-4 inches long, convex below, flat above, soft elevated longitudinal lines in the middle, marginal teeth small and barely visible to the eye”.

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Observations on the G.G. Smith Collection of Haworthia (1982)

G. G. Smith ‘s collection of Haworthia was donated to Kirstenbosch and the Compton Herbarium in 1950, together with an ostensible manuscript of a monograph, his basic collecting record, various catalogues of literature and odd notes. However, there was no indication of Smith’s overall view on the classification of Haworthia, or of any Intention he had for the genus at the time he abandoned work on it. On his death in February 1976, Dr M. Courtenay-Latimer obtained many remaining papers from his home. and also the Compton Herbarium became the repository on permanent loan of the entire collection belonging to the East London Museum. Among the papers Is an Immense number of detailed drawings by Dr Courtenay-Latimer of the kind which were used to illustrate Smith’s publications, as well as very detailed assessments of ‘species’. Smith accessioned all his plants individually and each plant was assessed on virtually every measurable character. It appears that Smith first considered whether a new taxon was indicated or not. and then made these numerical assessments against plants which either were, or were considered to be, existing taxa.

The papers show that Smith was in fact contemplating a whole new range of species and varieties. At the same time it is interesting to note his comment in a letter to the head of the Botanical Research Institute (as It is now named) in Pretoria. Here he says that trying to determine a species from one or two plants is a total waste of time. In a manuscript among his papers In which he concluded that the sections Obtusatae and Planifoliae were synonymous, he writes: ” In some cases with different plants from the same locality and even from the same cluster. it was possible to place some In each section.” This is a significant remark which collectors should note as even von Poellnitz described H. cymbiformis var. translucens and H. planifolla var. transiens from the same collection.

Smith seems to have been particularly Involved with the sections Trlfariae, Coarctatae, Obtusatae and Retusae as they then existed. In the section Obtusatae he had proposals for 13 new species, 18 varieties and two sub-varieties. All these are simply referred by the writer to H. cymbiformis (Haw.) Duval. In the Retusae he did not propose any new species but instead visualized 21 new varieties, two sub-varieties and a forma. In the case of H. nitidula v. Poelln. he had nine varieties in fact were drawn from the species H. mirabilis Haw., H. retusa (L.) Duval and H. emelyae v. Poelln. The accompanying illustrations show that H. emelyae v. Poelln, and H. mutica Haw. were both confused with H. pygmaea v. Poelln., while H. mutica and H. retusa were also confused.  In H. turgida Haw. Smith proposed seven new varieties. In the sections Fusiformes, Fenestratae, Loratae and Limipdae there were descriptions of one new variety in each; in the section Muticae that of one new species and two varieties, and in the Denticulatae one new species.

In the Trifariae there were proposals for four new species and 14 varieties in a species which is really not so particularly variable, i.e. H. viscosa (L.) Haw. It is in fact difficult to detect the differences in these supposed varieties from the photographs accompanying the descriptions. Finally in the Coarctatae there were descriptions of six new varieties of H. reinwardtii Haw., two of which actually belonging with H. coarctata Haw. This gives a grand total of 19 possible new species, 65 varieties, four sub-varieties and a forma.

Smith’s assessments involved detailed measurements and observations of as many as 56 different variables and should serve as a salutary lesson for any budding taxonomist. There is just no sense in arguing about trivia. The species are highly variable and in many cases are not clearly definable to the exclusion of other species. While each and every clone of Smith’s collection could ultimately have had a name involving three or four epithets, there is no justification for ridiculing this aspect of his work. Together with Dr Courtnay-Latimer, Smith left an herbarium record unrivalled in the Liliaceae and perhaps only by Dr L. Bolus’ equally invaluable contribution to a permanent record in the Mesembryanthemaceae.

Fig. 1 (top): GGS 2935 HAWORTHIA EMELYAE v. Poelln. From Uniondale – ‘H. pygmaea var. A. Smith’.
Fig. 2 (centre): GGS 3430 HAWORTHIA MUTICA Haw. From Bonnievale – ‘H. pygmaea var. B. Smith’.
Fig. 3 (bottom): GGS 3249 HAWORTHIA MUTICA Haw. From Stormsvlei – ‘H. retusa var K. Smith’.

Fig. 4 (top left): GGS 5061 HAWORTHIA MUTICA Haw. From Swellendam – ‘H. retusa var. J. Smith’.
Fig. 5 (bottom left): GGS 5377a HAWORTHIA RETUSA (L.) Duv. From E. Riversdale – ‘H. retusa var’. (H. geraldii Scott). A large clump.
Fig. 6 (top right): GGS 5377a HAWORTHIA RETUSA (L.) Duv.
Fig. 7 (bottom right) GGS 5377b HAWORTHIA RETUSA (L.) Duv. From E. Riversdale – ‘H. retusa var.’.

by M. B. Bayer
Photos by the author.
Nat. Cact. & Succ. J., Vol. 37/4 (1982) pp 105-106.

The Cape Flora and the Karoo (1984)

THE CAPE FLORA AND THE KAROO
A winter rainfall biome versus a fynbos biome!
by M. B. Bayer, Curator, Karoo Botanic Garden, Worcester
Veld & Flora March 1984

The humorist Groucho Marx when once propositioned said “for that you can include me out!” That is just how someone living in the Cape not within eyeshot distance of an erica, a protea or a restio, must feel — included out. Naturally one wants to be in on the show and Nordenstam’s1 statement that there is a “tendency to particularise the Cape flora” is a comforting one for those out in the cold.

Several recent papers on the Cape flora (Goldblatt2, Taylor3, 4 and Oliver, Linder and Rourke5) strengthen the exclusiveness of the club, and currently Cape flora and fynbos (sensu Taylor6) seem to be synonymous. Karroid species (non fynbos sensu stricto) are only called in when necessary to boost the numbers of species in, and stress the richness of, the Cape flora.

Geological pattern Peter Goldblatt points out that the correlation between the Cape floristic region and mediterranean climate is a loose one. But it is his concession that the Cape region follows a geological rather than a climatic pattern which is more interesting. This is not only because of the obvious relationship between Table Mountain sandstone and fynbos, but because geological considerations seem to have been lost in the recognition of the Karoo-

Namib region. This phytogeographic region extends from Angola in the north, to the south-eastern Cape and is the effective inland boundary of the Cape region. White’s Karoo-Namib2 covers the Kalahari sands, basement granites, bushveld granites and, predominantly, shales the Karoo system. and tillites of The paper by Oliver et al is a cruel shot in the eye, because in setting out to reappraise the boundaries of the Cape flora, only species typical of fynbos are used. A predetermined result.

Fynbos formation in new perspective There is no denying that fynbos is a “separate plant formation distinct floristically and physiognomically from the formations of the Republic”3 but it is time that its geological associations are brought into proper perspective. Oliver et al write of “tongues of vegetation” … rendering exact and simple definition of their (fynbos, Karoo and evergreen forest) boundaries very difficult. My contention is that such a definition is difficult because geology, and hence soil, overrides all the other ecological factors which operate to determine vegetation.

Winter rainfall should have been the natural choice in selecting an agent responsible for the uniqueness of fynbos, and one must ask why this is not done. Goldblatt skirts the issue and simply bases his Cape flora “solidly” on Acocks7, and includes non-fynbos vegetation types for practical reasons — in order to draw a rigid line about the Cape flora region. The area under winter rainfall is by-passed because it and the fynbos area do not coincide. Instead, there is a fairly abrupt end to the fynbos which coincides with the limits of the Table Mountain and Witteberg sandstones.

Currently the winter rainfall area is fairly well-defined by Poynton8 as extending in an arc from the mouth of the Orange River to Cape Agulhas. Poynton does not define “winter rainfall” but it is assumed to be where 60% or more of annual rainfall occurs in the winter. The zone of uniform annual rainfall parallels that of winter rainfall in the north, but widens southward and eventually ends between Port Elizabeth and East London. If that is the present situation, then what of the past?

Menace of an expanding Karoo Nature lovers and conservationists are concerned by shrinkage and loss of fynbos — and agriculturists by the north-westerly migration of the Karoo. Acocks10 paints a grim picture of the Karoo and semi-desert invading the rich grasslands of the Orange Free State and Eastern Cape. Although shrinkage of fynbos and expansion of the Karoo are not directly linked (the first is attributed to “mechanical” destruction, and the second to pastoral land use), there may be a connection. The future will become history and so then, what of the past?

The results of palynological research9 supported by other disciplines, shed a whole new light on the real Cape flora. It appears that as recently as 12-15 000 years ago, the world was experiencing a minor ice-age. During this time the system of mediterranean climate was situated northwards by as much as 6° latitude. This means that the northern limits of winter rainfall would have been in the north of South West Africa instead of at the mouth of the Orange River as it is now. Cyclonic winter rainfall would havebeen reaching across the southern Kalahari, across the Orange Free State and deep into Transvaal.

Shifting rainfall regimes Acocks gives a map which depicts the extent of Karoo elements, and these fit beautifully into the conceptof an extended winter rainfall region. Now it begins to make sense. The Cape flora is not just fynbos— it is a plant formation which coincides with the expansion and contraction of winter rainfall and all associated phenomena. As the winter rainfall zone has movedsouthwards, so has the Karoo shrunk accordingly. The flora of the Kalahari highveld, Afro-montane and Tongaland-Pondoland regions have advanced along the face of the retreating Karoo and advancing summer rainfall regime.

Acocks’ hypothesis of an expanding desert is true in the sense that grazing pressure particularly on summer rainfall grasses, has reversed the process. Non-palatable Karoo species have regained lost ground. Probably only because summer rainfall species competition has been reduced. Remotely perhaps because of a climatic swing back to a winter rainfall regime (heralded by the current devastating summer drought) or artificial aridification as a result of reduced ground cover.

With the possibility now established that Karoo is also Cape flora, a whole host of plant species can waltz into the limelight and take a bow. A winter rainfall biome can now be recognized within which other factors such as geology, altitude, latitude and longitude can operate. However, it is still important to explain adequately the vast difference in species endemism which exists between the north-west and the south-east areas of this winter rainfall biome.

Thoday’s 1925 map of drought severity in NW Cape This is remarkably easy because as long ago as 1925 D. Thoday10 in a study of Passerina presented a telling map illustrating the severity and incidence of drought. This shows that the north-western Cape (Namaqualand and Bushmanland) has to contend with extremely severe summer drought. Thoday’s map can be exterpolated to a glacial age with little imagination. Coupled with seasonality of rainfall, and history of climatic shift, we now have a scenario in which the Karoo can be properly related to fynbos. It can be suggested that high species endemism in the north west is due to geological and climatic extremes. Low endemism (?) in the Eastern Cape is because of relative equability of climate (rainfall) during glacial and post-glacial shifts.11

The fynbos derives its special place because of geology and sustained high winter rainfall, which impose further isolating mechanisms over location at the tip of a continent. The whole purpose of this little exercise is not only to gain access for a Karoo lover into a fynbos club. It is to find a foothold for a feeling that the Cape flora is a very ancient one — the concept of only fynbos representing a Cape flora reduces our capacity to observe and understand what we have and how we are to keep it. Fynbos is not an element which had advanced and retreated like an army. There has been a retreat with a rising sea level and constricting coastline as the glacial age passed, and there has been some change along the interface between summer rainfall and winter rainfall. But the fynbos has been reasonably secure on its geological base, and so has the core of species comprising the Karoo.

Stronger urge to conserve The endemnicity and distribution of many species such as in the genera Aloe, Commiphora, Pachypodium, Tylecodon, Adromischus, Crassula, Conopytum (and most of the mesem genera), Euphorbia, Asclepiadaceae, Geraniaceae and Oxalidaceae all support the wider concept of the Cape flora as a winter rainfall biome. This endemism suggests a permanence beyond minor climatic change (eg. Aloe can perhaps be argued back to the time of continental drift 140 000 000 years ago). Such permanence suggests that we need a still broader and stronger urge to conserve — or we will plough, bulldoze and trample away the florally greater equivalent of the great library at Alexandria.

REFERENCES

1. B. Nordenstam: Phytogeography of the genus Euryops (Compositae). A contribution to the phytogeography of Southern Africa. Opera Botanica 23; 1-79 (1969).

2. P. Goldblatt: An analysis of the flora of Southern Africa: its characteristics, relationships and origins. Ann. Missouri Bot. Garden 65; 369 436 (1978).

3. H. C. Taylor: Phytogeography of fynbos 13; 231-235 (1980).

4. – Is fynbos the natural climax vegetation of the south-western Cape Province of South Africa, in proceedings of the International Symposium on Vegetation Science, ed. A Schwabe-Braun, Cramer, Vaduz, p 385-391 (1981).

5. E. G. H. Oliver, W. P. Linder and J. P. Rourke: Geographical distribution of present-day Cape taxa and their phytogeographical significance. Bothalia (in press).

6. H. C. Taylor: Capensis in biogeography and ecology of Southern Africa, ed W. T. A. Werger, The Hague, p 171-229 (1978).

7. J. P. H. Acocks: Veld types of South Africa. Mem. Bot. Surv. S. Africa 28: 1-192 Govt. Printer Pretoria (1953).

8. R. J. Poynton: A silvicultural map of Southern Africa. South African Journal of Science 67: 58-60 (1971).

9. E. M. van Zinderen Bakker: The evolution of late-quartemary paleoclimates of Southern Africa. Palaeoecology of Africa 9, Balkema,Cap e Town, p 160-202 (1977).

10. D. Thoday: The geographical distribution and ecology of Passerina. Ann. Botany 39: 175-208 (1925).

11. R. M. Cowling: Patterns of plant endemism in the south eastern Cape. The Naturalist 27: 17-36 (1982).

Haworthia – Confusion Reigns Again (1986)

Printed in Excelsa 12:91 (1986)

Haworthia is a genus plagued by confusion of one kind or another and it seems now impossible to write about these plants without casting doubts on someone’s integrity or sanity.  The problem in the genus is not simply that there are very few herbarium specimens, or adequate descriptions and illustrations by which the various species can be typified. The various elements in the field are so continuously variable that it is difficult to decide where one species begins and another ends – but not so difficult.  There is some straightforward confusion as in the case of Haworthia margaritifera (L.)Haw. where Wijnands shows that H. pumila (L.)Duval is incorrect.  (Excuse my nomenclature – but this means it is incorrect for the species to which Duval attached the name [H. herbacea] – it is correct for the species to which Scott attached the name).

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Haworthia and Nomenclatural Confusion (1987)

Printed in British Cactus and Succulent Journal 4:45 (1987).

Haworthia is indeed a popular genus which seems to inspire a great deal of controversy and confusion.  One would have to be very thick-skinned to be able to ignore past history and not plead for forgiveness for similar transgression.  I was just busy trying to clarify, in my own clouded mind, the problem of H. pumila (L.) Duval, when I saw Will Tjaden’s little article on the subject in this journal (3:88, 1985).  Gordon Rowley in the same issue reviews the recent books on Haworthia and also mentions the H. pumila versus H. margaritifera debate.  Coming so soon on the heels of Fearn versus Cole and Walker versus Bruyns, it would be insensible for Bayer to take up the cudgels against anyone.

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