i7 
illustrated by the South African Flora . 
are closely allied and some single species are extremely variable, e. g. 
P. myrrhifolium , of which Harvey gives nine varieties that have been 
described as distinct species by various authors. Thotfgh the eastern species 
are, as a rule, distinct from the south-western, in some cases they are nearly 
related, e. g. P. lobatum and P. pidverulentum. Only one or two, e. g. 
P. alchemilloides , P. capitatum , are common to Natal and the Cape. 
P. inquinans , the parent of most of the ‘scarlet geraniums’, extends from 
Natal to Uitenhage. The general distribution of the genus, with its fairly 
numerous outlying species and greatest concentration at the Cape, is the 
chief point of interest, since it is paralleled in so many others and throws 
light on the question of the origin of the south-western flora. 
Oxalidaceae . 
The only genus is Oxalis , with more than a hundred species, again 
chiefly concentrated at the Cape, but with seven in Natal and seven in the 
Transvaal. 
O. cornicidata is a ruderal, common in subtropical regions. The 
Abyssinian species O. obliquifolia is very near the Cape 0\ convexida , and 
O. caprina , another Abyssinian species, is also found at the Cape. The 
genus illustrates generally the same features as Pelargonmm . 
Rtitaceae . 
Calodendron capense , the Cape Chestnut, is a monotypic species, 
a large forest-tree whose distribution is to be explained only by migration. 
It is found in all the eastern forests and has no near allies. Xanthoxylon 
capense (Fagara), on the other hand, illustrates exactly the same points as 
Kiggelaria (Bixaceae) described above. Sim (31) sinks all the forms in one 
species, but the xerophytic forms are widespread, the more mesophytic 
forms have restricted and discontinuous distribution. The genus is tropical. 
Toddalia lanceolata (eight stamens) is widespread from the Cape to Mozam- 
bique and Mauritius. Toddalia natalensis , four stamens, but otherwise 
very similar, is only found in the Eastern Province and Natal. Clausena 
inaequalis is a Natal and tropical species, allied to the Indian C. Willdc- 
novii. 
The Rutaceae of the south-western region are strongly scented 
xerophytic shrubs, very different in every way from the eastern forest 
species. There are nearly two hundred species in the south-west, belonging 
to nine genera, of which Agathosma includes about half. Only one species, 
Barosma lanceolata , reaches Natal. This marked contrast and differentia- 
tion between east and west in the family is very striking. 
Celastrineae . 
The genus Celastrus illustrates again our chief points. The tropical 
African species appear to be all endemic, with mostly narrow ranges, except 
C. senegalensis , which extends from Mozambique to the Mediterranean and 
eastward to India. The^twenty odd South African species are all different. 
C 
