VOLUME 14 :: January—October, 1952 Illustrations shown in ...

THE CACTUS AND SUCCULENT January, 1952
THE SYSTEMATICS OF CONOPHYTUM N.E. Br.
By Dr. A. TISCHER
Translated by E. Engler
When in the year 1922, N. E. Brown, by separation from Mesembryanthemum L, formed the genus Conophytum*,
about fifty species, that were adjudged to this genus, were known. Already Brown himself felt the need to group
these species according to definite characteristics. In the meantime, the number of described species and forms
has grown to nearly three hundred. The necessity for a systematic arrangement of this large number of species,
has prompted a number of scientists to suggest a division into groups and sub-groups. Such proposals emanated
from N. E. Brown, L. Bolus, Herre and especially Schwantes**. The most comprehensive systematics, up to the
present, was recently published by Schwantes in " Kakteen und andere Sukkelenten," year 1950, No. 5, and 1951,
Nos. I and 2. The work represents a continuation of his earlier systematic studies, but deserves special notice for
the reason that here, for the first time, attention is drawn to the limited geographical distribution of the members
of each group. According to these writings, conclusions in regard to the systematic affinity of a species can already
be drawn from the place of occurrence. At all events, for future finds, the systematic grouping will thereby be
considerably facilitated. It is regrettable, though, that Schwantes had only limited plant and flower material at
his disposal. Thus, a number of species could not be taken into consideration in the grouping, others were grouped
wrongly, due to insufficient knowledge of the flower. Nevertheless, all further systematics of Conophytum will
have to build on the findings of Schwantes.
According to the fundamental rules of modern Botany, for the grouping of species, it is, in the first place, the
sex characteristics which count. In future systematic examinations of Conophytum, we shall have to pay attention
to these principles even more than in the past. In this task the examination of seed, ovules, or even of the chromosomes
will perhaps bring us knowledge of affinities which we were not able to have up to now. First of all, we
shall have to concentrate chiefly on the characteristics of the flowers. I myself had the opportunity, during the
past years, to study not only an extensive plant material of this genus, but also to observe the flowers of a large
number of species. I was assisted in my work by means of hints, plants and literary material, particularly by
Messrs. Bates, of Hounslow, Captain Dunne Cooke, of London, Dr. de Boer, of Haren, Herre, of Stellenbosch,
Jacobsen, of Kiel, Professor Schwantes, also of Keil, Graessner, of Perleberg and Triebner, of Windhoek, to whom
I would extend my special thanks here.
My studies enable me partly to supplement the systematic findings of Schwantes, partly to amplify them, so
that I can now submit suggestions for a systematic grouping of all species known to me as having been described.
The body shapes of the Conophyta allow them to be traced back to a number of fundamental types. Already
in 1922, N. E. Brown set up a table of types, which comprised types of body shapes***. The large number of species
and forms, which have become known meanwhile, make a still more thorough characterisation of the fundamental
types desirable. I have, therefore, enlarged the number of types set up by Brown and established a new type table.
In the following systematics of the genus Conophytum the types belonging to the groups have been mentioned
individually.
The systematics given in this work does not replace a key to the species of Conophytum. But, in order to
facilitate the ascertainment of species for the benefit of those who are interested scientifically, or of friends of these
attractive plants, I have added to each species, in parenthesis, the colour of the flower and the type of the type table.
In this connection, w means white, c—cream or ivory, y—yellow, o—orange, co—coppery or salmon coloured,
r—red, rs—rose red or rosy, p—purple or magenta, v—wine coloured. For instance (y/10) means " flower yellow,
type 10 ; (r36/39) means flower red, type about 36 and 39. The figure indicates only the contour of the little
bodies, seen laterally, but does not signify the size of the bodies, which may be larger or smaller.
CONOPHYTUM N.E. Br.
Sub-genus ; Fenestrate N.E. Br.
Plants with short stems, or stemless, forming cushions. The small bodies — cylindrical to obconical, flat to
convex above, partly ± bilobate due to small fissure on the upper surface, lobes flat or slightly convex, not keeled,
* The Gardener's Chronicle 1922, p. 198 and 450.
** N. E. Brown I.e., Schwantes in Gartenflora 1927, page 424, L. Bolus in Notes on Mesemb., Part III, H. Herre
in the Cact. and Succ. Journal of Gt. Britain, Vol. 10, page 56 et seq., N. E. Br. in the Journal of the Cactus and
Succulent Society of America, Vol. II, page 425.
*** The Gardener's Chronicle, Vol. LXXI, pages 214 and 450.