Author Archives: Bruce Bayer

Volume 1, Chapter 3:- The case of Haworthia incurvula V.Poelln. – an up-date.

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This article was first published in Aloe 36:34, (1999) and is now rewritten in part to accommodate some new collections and a conclusion modified accordingly.

The problem:-
Von Poellnitz described Haworthia incurvula (Feddes Repertorium 31:85, 1932), from specimens ostensibly from Grahamstown, sent to him by Mrs. E. Ferguson.  The important elements of the description are.. “leaves about 40, barely 20mm long, up to 12mm wide, broad ovate-oblong, without teeth, hairs or spines, on the face almost flat and inconspicuously turgid towards the apex, on the back convex and towards the apex with a rounded keel, very rarely inconspicuously double keeled, pale green and traversed by greenish longitudinal lines, which are somewhat anastomosing, some of which reach the pellucid tip, which is by no means abruptly pellucid”.  Von Poellnitz (Fed.Repert. 41:203, 1937) acknowledges that this is the plant illustrated in Flowering Plants of Southern Africa 9:t356 (1929), which is there identified there as H. cymbiformis var. planifolia (Haw.)Baker.  Again (Fed. Repert.44:233, 1938) he acknowledges the illustration given by J.R.Brown (Desert Plant Life 8:45, 1936).  Here he gives.. “the exact locality is Pluto’s Vale in Albany district, between rocks and bushes”, citing R.A.Dyer as the source (Botanical Survey of South Africa, Memoir 17:98, 1937).  Von Poellnitz adds here that.. “in vigorous cultivated plants the leaves are less incurved or almost not at all”.  He was uncertain what its affinities were and placed it in the section Muticae.  However, it should be noted that Von Poellnitz placed the synonymous H. planifolia (Obtusatae) and H. cymbiformis (Planifoliae) in different sections too.  This was despite his confession and obvious in his writing, that he did not know the difference between them.

  • Grahamstown and environs: 1-Thornkloof, 2-Helspoort, 3-Glen Craig, 4-Fort Brown, 5-Pluto’s Vale
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Volume 1, Chapter 4:- Haworthia cooperi and Haworthia bolusii var. blackbeardiana.

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One of the greatest difficulties in Haworthia is that of trying to recognise discrete species.  This translates into confusion which can be attributed to writers.  The initial source of confusion is without doubt the nature of the plants themselves, and this is not a problem confined to Haworthia.  The species are often not easily recognisable and discrete entities.  I abhor the statement that the genus is in a state of active evolution, but this does at least seem to convey a message that readers understand, even if it is somewhat hackneyed.  My observations on Haworthia are based on a definition of species as a system of living organisms which are continuous in time and space.  In my New Haworthia Handbook, I suggested that a primary problem lay in separating H. bolusii  and H. cooperi, and for the purposes of that work I largely discounted the secondary problems.  My first concern was to identify core areas and names as working postulates.  This did not mean I was unaware of lesser problems contained within the recognition of those two species.  The purpose of this paper is to present my current understanding of the problem.

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Volume 1, Chapter 5:- The Haworthias of Kaboega.

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M B Bayer, 16 Hope Str., 8000 Cape Town.
Ian Ritchie, Box 44, 5850 Somerset East.

Introduction
Kaboega (also spelt Kabouga) is now an assemblage of farms (De Plaat, Wilgerfontein, Vygeboomfontein, Klipfontein) nestled against the north slopes of the Zuurberg mountains, north of Kirkwood.  It is only about 15km away from Kirkwood as the crow flies, but 150km away by road.  Oudekraal is about 20km east and it is the source of Haworthia angustifolia var. baylissii and Gasteria baylissiana.  There are several records of Haworthia for the Kirkwood area, and von Poellnitz named H. stiemiei (Regarded as insufficiently known and not recognised by Col C.L. Scott or myself) from there.  He also identified plants from Kaboega and Uyepoort, both described as “at Kirkwood”) as H. altilinea var. denticulata (Haw.) V. Poelln.  These plants are all in the melange that I attribute to H. cooperi var. gordoniana (the subject of another long essay).  The Kaboega farm lies on the Kaboega river which drains an area of about 1m ha and then flows through the long Kaboegapoort into the Sundays River just north-west of Kirkwood.  The terrain is very broken with the sandstone Zuurbergs themselves dominating the southern boundary at about 850 to 950m above sea level.  The lowest point on the farm is at about 300m and the northern lesser shale or dolerite peaks reach 550 to 650m.  The vegetation on the sandstones is Dry Mountain Fynbos.  North of this is Karoo Valley Bushveld.  Thus Kaboega is at an ecotone of the karoid veld, Eastern Cape grassland and the Noorsveld (Euphorbia thicket) of the Jansenville area.

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Volume 1, Chapter 6:- Summation – and a new solution?

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The five papers in this book represent analyses and discussion of a large number of collections revolving principally around the problems of the Eastern Cape Haworthia species.  The paper regarding H. mucronata does provide some insight into the overall problem.  The citations by Von Poellnitz for varieties of H. altilinea and H. mucronata indicate just how difficult it is to differentiate between species such as H. bolusii and H. mucronata, from their respective geographic locations.  In the case of H. cymbiformis var. incurvula; then in the case of H. cooperi, H. bolusii var. blackbeardiana, H. aristata and H. decipiens var. pringlei; then H. cooperi, H. gracilis and H. cymbiformis; and finally in the case of Kaboega; it is evident that a better solution can be sought.

During the course of the analyses, it became evident to me that a gracilis-like element is present in every one of the cases.  It is less evident in the case of H. mucronata, because I have not presented the data and also because I have not collected sufficiently either.  Certainly H. mucronata is closely allied to cooperi, cymbiformis, blackbeardiana and to decipiens.  However, it is also very closely intertwined in H. arachnoidea and a lot more field observations are required to determine what its archetypal kinships may be.  They may be the same as for cooperi and cymbiformis.  Regardless whether or not this is so, the question still arises:- If gracilis is the archetype for so many species  which the evidence leads me to suggest it is, what then is this element I call gracilis?

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Volume 2, Introduction and Acknowledgement

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I must explain why I wrote and why I write. Reading and writing are inextricably related. I observed Haworthias, I read about them, and I wrote about them. This was to organise and record what I had learned, to refute what I deem to be wrong and to seek verification of the new. I never did feel adequate to the task of formally revising Haworthia.  The fact that I did so was because I was asked to. It was quite clear to me that however inadequate I was, there was nobody else who was going to do it any better. The work (Haworthia Revisited, 1999) was premature in the light of what really needs to be known if a good classification is going to emerge. It is a considerable disappointment to me that much of my writing has not served to guide other writers as I hoped it might. The forewords to Breuer’s two volumes by messrs Ihlenfeldt and Smith confound my sense of what is true that I truly wonder if there are readers who are anxious to share that same ideal. Sometimes I wonder if my writing has served any greater purpose for which it may have been intended other than to help me organise my own ideas and activities.

Species identification in Haworthia is difficult.  This is not a new statement, but simply now a self-evident truth which is becoming increasingly so as I extend my field experience.  Recently someone commented on the odd flowering time of H. pulchella var. globifera, commenting that the flower was even unusual.  The species pulchella was not yet showing signs of flowering, whereas the odd H. monticola var. asema was budding.  The similarities of that variety to globifera in terms of leaf colour and shape, proliferation and flowering time are striking.  I later looked more closely at the flower of globifera and found that, in the clones I had available, there was no visible difference whatsoever, between the flowers of globifera and H. cymbiformis var. incurvula from Pluto’s Vale.  My collections of the latter were also not all in flower, and quite clearly flowering time (useful as it is) is no more an absolute than can be stated in Stephen Gould’s paraphrased…”The strongest statement that one can possibly make in biological science is ‘hardly ever'”.  What to say of the similarity of the flowers in two elements which could hardly be further apart in the sense that classification is applied in the genus.

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Volume 2, Chapter 1:- The curious variability of Haworthia floribunda

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M.B.Bayer, 16 Hope Str., 8001 Cape Town.
R.W.Kent, 16206 Rostrata Rd., Poway, CA92604.

Introduction:-
Haworthia Revisited was drafted in 1996, and since then the first author has undertaken a number of field excursions in an attempt to clarify uncertainties.  The putative nature of species of Haworthia as recognised by Bayer (listed in Haworthia Revisited, Umdaus 1999) and the importance he attached to geographic distribution are stressed in all his publications.  This is because these so-called species seem to vary continuously with one another in that context of geography.  Classification seeks to portray relationships and origins.  Hence when a species has been recognised, a cognitive attempt has been made to speculate on phylogenetics, where distribution must be significant.  In the case of Haworthia floribunda this proves rather difficult, and this article is a discussion of the relationship of this species to its possible relatives.  The point we do make is that the Linnaean binomial system, as well as cladistic methods, seem neither to deal with nor portray the problem of reticulate relationships.  In other words, the nomenclatural system and the way we classify plants and analyse their relationships assumes linear dichotomy in those relationships.

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Volume 2, Chapter 2:- A population of Haworthia magnifica/maraisii

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Introduction:-
After writing Haworthia Revisited in 1996, I became aware of just how inadequate readers seem to be to the task of assimilating all the available literature on Haworthia, in the botanical and intellectual climate in which we live.  It seems as though the more information we have the more confused we become.  In order to generate the material needed to disprove or fortify my classification hypothesis, I have spent a further considerable amount of time in the field and in cultivating plants from seed.  Unfortunately the editorial support and speed of publication has not kept pace with my own effort and much of my writing and my evidence is still in manuscript form.  This short essay was therefore to put forward only a little more evidence to show just how complex plant species are – not necessarily only in Haworthia.

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Volume 2, Chapter 3:- Where to Haworthia limifolia

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(This chapter was published in Aloe 40:2:41-52, 2003, and I have added an addendum with further explanation and discussion).

My first experience of this species Haworthia limifolia, was with a plant brought from somewhere in Zululand by my late uncle Frank Bayer.  He was involved with malaria control in then Zululand and Northern Natal.  He must have given the plant to my father while we were staying at New Hanover during the period 1950 to 1954.  I have always been attracted to Haworthia, but I did nothing more than admire the plant as it flourished in my mother’s care.  I never really concerned myself with the origin of the plant other than recalling my uncle telling that he had stopped for lunch by the roadside, and his Zulu assistant had come back to the car with the plant.  I had thought he said “near Nkandhla”, while my father later doubtfully remembered “Nongoma”.  It could have been “Ithala”.  I recall now that my uncle was stationed at Vryheid during that period and this is a small way inland from either Ithala or Bivane Dam, which feature later in this article.

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Volume 2, Chapter 4:- Haworthia limifolia var. arcana Smith & Crouch

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Haworthia limifolia is something of an enigma in that both it and Haworthia koelmanniorum are geographical rather isolated from the rest of the genus.  The latter is confined to a small area around Loskop Dam and Groblersdal in what was the old Transvaal province.  H. limifolia is much more widespread and occurs from the southern Kruger National Park southwards through Swaziland in to Northern KwazuluNatal.  It was described by Rudolph Marloth from a specimen very loosely said to have come from “west of Delagoa Bay”.  No one has ever managed to tie the species down in terms of geographic origin, and the Flowering Plants of Africa (55:24-29, 1997) description of the typical var. limifolia, depicts it as the var. gigantea.  My own fieldwork and observations of material of known field provenance show that this var. gigantea and the var. striata are surely synonomus.  Neither of them could truthfully said to be from “west of Delagoa Bay”

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Volume 2, Chapter 5:- The White Widow Reunion – Haworthia mutica

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During my early years with the Karoo Botanic Garden, in fact it never really got any better, my time spent looking for Haworthia was largely my own.  This meant hasty weekend trips, or looking for haworthias secondarily to other things and more general goals.  Also it was a question of scale.  I needed to see populations and plants from across the entire distribution range.  So those years were spent rather as reconnaissance and in checking all the herbarium and other records.  I came across a letter among Major F.R. Long’s papers which put me on the track of a Mr P.L. Meiring of Bonnievale, south-east of Robertson.  This was a copy of a letter from Meiring to Triebner in Windhoek arranging for the collection and purchase of an Haworthia from Drew Station.  The result was that 200 plants were sold for the huge price (for those days) of 1s each – allowing for inflation this would have been worth about R14ea in today’s currency.

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Volume 2, Chapter 6:- How to understand Haworthia mutica var. nigra

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(When I wrote the first part of this essay, I was anticipating completing it in three parts.  However, I was also in the process of exploring more widely and thoroughly, and the problem and its explanation seemed to grow exponentially.  The result was seven essays, and they are presented here as close as possible to their original format.  The purpose is to show how a classification should have predictive value, and how an understanding of plants can develop, or fall apart, as more information accumulates. The seven parts were published in Haworthiad 17:1:24-32, 17:2:53-54, 18:1:21-33, 18:2:52-57, 18:3:92-101).

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Volume 2, Chapter 7:- Continuity of Haworthia on the Zuurberg

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This problem of continuity is one I seem to have difficulty in conveying to my readers and listeners.  The difference between one species and another is a discontinuity and, if we believe in evolution, it is the resultant of a break-up of continuity in its ancestral parent species.  The “model” we have in our minds, is of progressive change from one recognisable entity to another by evolution.  Geographic distribution and re-distribution are key elements in this process.  But we do not seem accept this in the way we try to classify plants or interpret classifications.  Apart from recognising that change could be gradual and therefore manifest continuity, the change may be from a complex variable system which contains different levels of continuity within itself, and not from a simply understood uniform ‘ancestor’.

The result is that in a genus like Haworthia, which is by no means exceptional, the differences between species i.e. the discontinuities between “species”, may be very difficult to either recognise or rationalise.  It in fact becomes a statistical operation in which all the characters should be involved i.e. multiple variate analysis.  If all the characters could be measured and quantified it is statistically possible to subject all the data so obtained by one of several statistical methods to measure “distance” and “significant difference” between groups of plants which we want to ascertain are species, varieties or even just hybrids.  The process of “cladistics” is the use of a system to generate a branching “tree” of relationships base on characters which are also evaluated and loaded for chronological priority (primitive versus advanced).  In using such a mathematical package, it is pretended that the classification becomes “objective” and hence replicable to satisfy the scientific requirement.  In my estimation, the cladistic process assumes that a two-dimensional “tree” adequately represents the spatial and temporal changes of evolutionary processes, and it does not work.

Somebody might one day try to apply such methods to Haworthia and I say “Good luck to you”.  My experience of characterisation and variation in the biological systems I have experience of, and including Haworthia, suggest to me that sensible, practical, experienced “eye-balling” will prove the better bet.  Ultimately in Haworthia, I expect that technology and cladistic methods will be testable on the result of my classification.  This is not a conceited and arrogant claim.  It is a simple reflection on what classification actually is and what it is for.  Much of botanical classification has been done by amateurs with no, or minimal, specific training and qualification for that field at all eg. G.W.Reynolds, L.C.Leach, T.L.Salter, J.Lavranos, C.L.Scott, G.G.Smith, M.B.Bayer etc.  Their classifications form the basis of many scientific observations, sometimes by scientists who have no conception of the significance, or insignificance of the names they use or what they may actually mean.  The classifications may have little to recommend them except the fact that they appear to conform to the approved nomenclatural style.

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Volume 2, Chapter 8:- Ecotypes in Haworthia

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With T.Dold, Selmar Schonland Herbarium, Grahamstown
This essay was published in Aloe 40:10, 2003. Minor additions are made here.

Introduction:-
By way of introduction it is fitting to repeat Dyer’s (1937) note on the Karroid Scrub of the Albany Division..”Pluto’s Vale and Hell’s Poort, names suggesting places of an unenviable reputation, are on the roads from Grahamstown through the Fish River valley to Kingwilliamstown and Bedford respectively.  Certainly very hot passes during the summer, they are nevertheless the homes of many botanical treasures, particularly succulents.  Several species of Haworthia are present (in the Albany division) but the soft leaved ones are usually found under the protection of rock ledges or scrub.  Pluto’s Vale is the home of two rarities, H. incurvula and H. tenera, both described recently by Von Poellnitz.”

The genus Haworthia is fairly difficult to classify, but Dyer’s words reflect the uncritical way in which any new species or variety is accepted into the literature.  Bayer (Aloe 36:34, 1999) discusses the two ‘species’ noted by Dyer and the complexity of their relation in Pluto’s Vale.  Bayer did not deal with the geological factors which might underlie their relationship, but this is implicit in the various books and papers he has authored and the reliance he has placed on geographic considerations.  In a new publication (see chapter 7) Bayer has also explored the relationship of Haworthia species on the northern slopes of the Zuurberg in the Kaboega area.  Here it is evident that geology and habitat are key factors in determining relationship between similar elements to H. incurvula (H. cymbiformis var. incurvula) and H. tenera (H. gracilis var. tenera).  In both cases the same key species viz.  H. cooperi (to include H. gracilis) and H. cymbiformis, are involved.  As in the case of Pluto’s Vale, the species, H. gracilis comes into question too.  This latter species has a questionable taxonomic history, but it was at the last considered to have originated in Helspoort (Afrikaans) to the north-west of Grahamstown.  While mentioning here, based also on recent publication of a possible type illustration (Breuer, 2000), that it may not have come from Helspoort at all, and may in fact be synonymous with what Bayer (1999) has taken to be H. aristata.  As discussed in “Haworthia Update”, there is a problem with the recognition of the Helspoort “species” in the face of the broad range of variant populations which constitute H. cymbiformis, H. cooperi, H. bolusii, H. gracilis and H. aristata and all the varieties associated with them.  A recent excursion was made to Helspoort to establish if the variation of the Zuurberg, Pluto’s Vale and the Baviaanskloof Haworthias was also evident.

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Volume 2, Chapter 9:- New Names and Combinations in Haworthia

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(This essay was published in Haworthiad 16:62, 2002.)

Introduction

Subsequent to my revision Haworthia Revisited (1999), I have done much more fieldwork, particularly in the Eastern Cape. This has revealed even more striking evidence of the intense inter‑relatedness of the so‑called species in Haworthia. Classification and revisionary classification is a sampling process.  As this progresses and more material is collected, so the classification firms up.  A extensive discussion explaining the following combinations and two new varieties is provided in “Haworthia Update Vol.1″ and an insight into the taxonomic problems to be solved is provided by the illustrations with another article, “Small Hairy Things”, elsewhere in Haworthiad.

My classification had some problem areas that were anticipated to a degree in Haworthia Revisited.  The following sentence appears in the discussion of H. cymbiformis var. transiens: “Thus H. mucronata can be allied with equal facility to either H. cymbiformis or H. cooperi, when in fact in the field it is more intimately related to H. decipiens.  The location of this note is a powerful reminder that distinctions between species are highly blurred and that alternative solutions are possible.”  I also make repeated references to the nature of the relationship of species and variants.  Many of those are specific to, or apply to, or are predictive of the following changes.  The basis of the following combinations is thus laid in Haworthia Revisited.

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Volume 2, Chapter 10:- Small Hairy Things

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(This article was published in Haworthiad 16:43, 2002.  Since then I have implemented name changes and I indicate these in bold type.)

When I have written about Haworthia, I have generally taken as a subject a particular species, in the sense that people regard a species as a kind of thing universally and unmistakably recognisable.  It is not always easy to find such things in the lower life forms, and this is also true for the sub‑genus Haworthia.  Here I am just writing about a few odd plants, without going into the many ramifications that are actually involved.

I am also using the classification, and system, rationalised and explained as best I could in my book “Haworthia Revisited” (1999).  Since that was written, I have been on many more exploratory journeys and have learnt a lot more.  Much of this new information has been published in “Haworthia Update Vol.1”.  There are several essays there, one devoted to the Baviaanskloof and one to the northern Zuurberg (Kaboega).  I explain that the name H. gracilis is probably redundant (I limit its use to H. cooperi var  gracilis as it occurs at Helspoort, Grahamstown. It may actually be better to regard most of the Baviaanskloof populations all as one species ‑ variants of a greater species that will be H. cooperi. I will implement the necessary name changes in another paper (This was done in, and the article is copied, in a preceding essay).

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Volume 2, Chapter 11:- Some of the interplay of H. arachnoidea and H. mucronata

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If any two species present a particular problem for the taxonomist in terms of their perceived variation, it must be these two.  I wrote a short article discussing this in respect of one particular population of H. arachnoidea (Aloe 38:76, 2001).  I also wrote on the same problem in my book “Haworthia Update” Vol.1 (Umdaus Press, 2002).  Despite some of the things I said there, there is still some misunderstanding expressed in informal communication regarding my approach, not only to the recognition of varieties, but to the interplay between what have been perceived to be different species.  One of the complaints is that if I do not recognise some of the new varieties described by other authors, my own varietal taxa should not be taken seriously.  In my Aloe article I wrote… “I have used varieties simply as a communication and descriptive tool to suggest lesser nodes and connections between what I think may be species”. In my revision (Umdaus Press, 1999), I wrote…”Lesser ranks should not be taken too seriously…”.

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Volume 2, Chapter 12:- Haworthia rossouwii VPoelln. and the demise of H. serrata Bayer

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This appeared as an article in ALOE 38:31 (2001).  Unfortunately there was a problem with illustrations and captions and these are corrected here.  A comment is also added as an addendum to respond to criticism by I.Breuer published in Alsterworthia 2:13(2002).

Introduction:
I described Haworthia serrata in 1973 (Jl S.AFr.Bot.39:249, see Figs.1) from Oudekraal, southwest of Heidelberg.  I commented then on the wisdom of describing a new species when “the recognition, estimation of taxonomic rank and circumscription of elements in Haworthia…” was so problematic.  The new species was said to resemble H. emelyae var. multifolia (Figs.2).  In respect of its distribution, I said it was closest to H. heidelbergensis at Heidelberg (Figs.3 JDV87/1) and as at Matjestoon (Fig.4 JDV87/3), and also to H. sublimpidula at Swellendam (now known to be H. floribunda var. major (Fig.5 MBB6859, taxonomically with little connection to H. rossouwii).  The implication was that it could have been taxonomically related to those elements in terms of geographic distribution.  I was still puzzled by the relationships of H. serrata when I wrote (New Haworthia Handbook :55, 1982) that collections by C.Burgers from the Coastal Limestones might throw more light on the matter (Fig.6 MBB6985 H. mirabilis var. calcarea).

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Volume 2, Chapter 13:- A trip to Bredasdorp

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This essay was published in Haworthiad 16:86, 2002.

I wrote an article about Haworthia rossouwii in Aloe 38:31(2001), in which I resurrected this old name to replace that of my own H. serrata.  This was necessary because I had found this plant (because of its localisation and its abundance there, it is better to say ‘this species’) at two places near Bredasdorp as opposed to where I had described my species from near Heidelberg.

One needs to know something about the geography and geology of the Southern Cape (and the Overberg as a part of it is also known) to really follow all the ramifications of any discussion about Haworthia, including this one.  In fact one needs to know a whole lot more, and I will also try to explain that and its implications for the collector and Haworthiophiles.  This “whole lot more”, I will call the Corporate Mind because it includes so much – so remember CM!  If I regard H. rossouwii as a species, I have to consider all the plants and all the places where they grow in order to determine the nature of this particular system of living things.  As I explained in my article, there is a problem with the fact that little is actually known about the Haworthias of the Overberg.  They occur in small populations scattered over a fairly wide area which has been heavily impacted on by agriculture.  Thus about 90% or more of the Overberg is now wheatfield or pasture.  Like Gasteria carinata, which is also a Southern Cape species, Haworthia is associated with rocky outcrops and thus also with the geographical erosion and drainage systems of the area.  It is quite probable that cultivation has had relatively very little impact on Haworthia in terms of actual available and suitable habitat.

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Volume 2, Chapter 14:- Explaining the name Haworthia intermedia VPoelln. and others

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Recently a cybernet note suggested that someone had a good understanding of the taxon/species, H. intermedia VPoelln.  That same writer has been a bit casual in describing new varieties, and in explaining what he actually means when he has used the species epithet accompanying them.  Understanding is a very relative term.  It may be extraordinary in terms of people who do not deal in the subject at all, high in relation to the knowledge level of the people with whom one is in ordinary contact and it may be very low in relation to people deeply involved in the subject.  It may also be quite negligible in terms of truth and ultimate reality.  With this in mind, I am going to take an opportunity to explain my own use/misuse of the epithet “intermedia“, and change it.  For several years I have been plagued by articles and statements in Haworthiad (and elsewhere), which are not strictly true.  In fact this distress goes back to correspondence with, and publications by, Col. C.L. Scott starting in 1965.  So when Dr Urs Eggli recently kindly stated to me his approach as follows:-

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Volume 2, Chapter 15:- Electron Scanning Photographs of Haworthia leaf surfaces

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Many years of experience have left me very skeptical of botany and botanical science, and particularly of writers who masquerade as taxonomists.  This is reflected in much of my writing and in these essays.  One of the difficulties I have had is in trying to understand why botanists tend to regard species as quantum units which are distinguishable from one another unless some taxonomists has made some statement to suggest that they are not.  Non-botanists are further beyond the pale.  This brief essay is to demonstrate that I have not found vaunted sophistication and technology of much assistance in better understanding the relationship of Haworthia populations to one another.  Often references to such technology are used as subterfuge by authors who should not be engaging themselves in classification at all.

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Volume 2, Chapter 16:- Nectar Sugars in the Alooid minor genera and a need for another model

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A paper, “Infrageneric classification of Haworthia (Aloaceae): perspectives from nectar sugar analysis”, concerning the analysis of such sugars in Haworthia, Astroloba and Chortolirion was presented at the XV!th AETFAT Congress in Belgium in 2000, by G F Smith. B-E van Wyk, E M A Steyn and I Breuer.  The proceedings of this Congress were published in Syst. Geogr. Pl. 71:391-397 (2001) and the particular paper by Smith et al was reprinted in Alsterworthia International 3(3)9-12 (2003). These authors comment on the taxonomic difficulties in trying to determine true generic limits in the tribe Alooideae of the Asphodelaceae and presented analyses of a limited number of taxa from the tribe.  I, in turn, want to use that paper to show why the difficulty persists.

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Volume 2, Chapter 17:- Species and varieties listed

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The following list follows the order in which specimens should be housed in the Compton Herbarium, National Botanical Institute, Kirstenbosch.  This list has a few amendments to that published in Haworthia Update 2 ca2006.  Gordon Rowley published a list of cultivar names in Alsterworthia to more formally recognise so many names that are useful or informative to collectors.  The object of classification is really to synthesise and generalise about plants.  As Dr Eggli stated, he feels he can attach little weight to any classification except in terms of the understanding he gains for the plants he has seen and knows.   So this list of mine is the product of my understanding of the plants I have seen and grown and conveys this information in respect of natural populations.  Among the many new names that have appeared subsequent to my 1999 revision, most simply precipitate collectors back into the good old days when the correctness of any name depended on its source i.e. one was sure of a correct identification only if the plant came from the author of the name or a very close source.  There are of course many plants in cultivation that do still carry their original and correct names and Gordon Rowley has listed many of them. They do convey an understanding of the history of Haworthia collecting but largely they are simply labels in the format of two latin names and seldom convey any information that such a scientific label suggests.   Gordon Rowley in private communication also humorously commented on the fact that MBB changes his mind. I cannot apologise for this because the fact is that I cannot even to pretend to understand the complexity that I see.  It has been difficult to write some of the preceding chapters for that very reason and I am very dubious that readers will necessarily be able to relate to what I have produced.  Certainly the authors of recent new names do not take my work serious and the attitude is quite mutual.  Many of the names are attached to my own records and are an essential part of the process whereby I arrived at my list.  In respect of virtually every new name I have seen, I am able to include it in this formal summary and account of species that have some rational reality.

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Volume 2, Chapter 18:- Bayer Accessions

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Bayer Accessions

A plant classification is essentially based on herbarium record, which is the prime means of verification.  However, it is not practicable for such a record to embrace all records nor record all the variation that has been observed.  In recent time, I have not deposited new material and the only record of accessions other than living specimens, is a photographic one.

This record of my collections is in four parts:-

  1. Un-numbered herbarium specimens.
  2. Collections under Karoo Botanic garden numbers (KG).
  3. Collections in a personal register (MBB).
  4. A record of J.D.Venter numbers for MBB collections

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Volume 3, Chapter 1:- Haworthia mirabilis, and the interface with Haworthia maraisii

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The problems of species classification of Haworthia should now be well known to all enthusiasts of this interesting genus.  I have proposed and maintained, with cosmetic changes, a nomenclatural system for it since 1975.  It is a system with which I have managed an extensive collection and herbarium record, and I know it works within the limitations imposed by the evident fractal nature of “species” and their variability.  In this paper I would like to expose these limitations with respect to the concept of two species viz. Haworthia mirabilis, and Haworthia maraisii, where there may be only one. (In the original hardcopy publication of this article, the illustrations are all captioned H. maraisii when it would have been sensible to have used H. mirabilis).

In most discussions concerning the classification of Haworthia, participants have suggested that there are too many species and that some of them should be “lumped”.  On the other hand, there have been several writers who, as prospective taxonomists and experts on the group, continue to expand the range of entities at the formal rank of species and varieties despite all the evidence and indications that this could be an endless path leading nowhere.  My own inclinations have been to minimize the number of species and to use varietal rank in two ways as a communication medium.  One is that I have tended to reject varieties of older authors which I did not think had a strong enough geographical base, but also recognizing that there is nevertheless some information inherent in such names.  Often I felt these varieties simply expressed the variability in a way that was insignificant with respect to the species as a whole.  Two, is that I have described some new varieties to provide names for morphological variation that I consider is new and previously unrecognized, accepting that these names should perhaps not be immortalized either.  Thus my proviso has been that these new varietal names should not be taken too seriously.  As far as the number of species is concerned, I know full well that there could be fewer species.  I get caught up in the problem of identifying a “species” in a strict botanical definition of the word, as opposed to the need for “names” as a way of simple communication about the plants in the amateur fraternity.  Because of the problem of similarity and continuity, the elimination of names becomes similar to that of falling dominoes and the question then arises of “where does it end?”  My classification should not be confused with a system of names intended for horticulture or for trade.  But neither do I think such a system should adulterate a formal botanical one.

Therefore, underpinning this presentation is a definition of a species as dynamic systems of living organisms morphologically, genetically and even behaviorally, continuous in space and time.

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