Origin of the Angiospermous Flora of South Africa. 323 



Crassulacece, Ficoidece, fleshy Ascleinadece, Liliacece {Aloes) and 

 Euphorhicey And further on, p. civ : " The many bonds of affinity 

 between the three Southern Floras — the AustraUan, Antarctic, and 

 South African — indicate that these may all have been members of 

 one great vegetation, which may once have covered as large a 

 Southern area as the European does a Northern. To what portion 

 of the globe the maximum development of this Southern Flora is to 

 be assigned, it is'vain at present to speculate, but the geographical 

 changes that have resulted in its dismemberment into isolated 

 groups over the Southern Ocean must have been great indeed." 



The same caution in dealing with this question is exercised by 

 Engler in his monumental work "Die Entwicklungsgeschichte der 

 Pflanzenwelt seit der Tertiarzeit " (1879, 1882)), and even recently 

 he has again (Engler, 1903, p. 35) expressed himself to the effect 

 that the origin of the isolated types, which are restricted to South- 

 West Africa, but are represented in other countries of the Southern 

 Hemisphere by allied types, constitutes a great enigma. The 

 frequently quoted example of the distribution of the genus Gingko, 

 which is now only found in Japan and China, while in former 

 ages it was very widely distributed, gives us a hint as to how little 

 value we can attach to speculations which are not supported by 

 palseontological evidence, and since palaeontological evidence is 

 practically absent for the former distribution of the Angiosperms 

 in the Southern Hemisphere, there is double caution necessary 

 in accepting conclusions from our knowledge of the present 

 distribution of plants, unless they are supported by facts derived 

 from palaeo-zoology and geology. 



That many of the types, more or less restricted to South-West 

 Cape Colony, are of great antiquity seems to be beyond dispute, but 

 in order to get an idea of their origin we must first of all settle the 

 question whether their sojourn in South Africa dates far back, 

 geologically speaking. Any theory accounting for the origin of the 

 South African Angiospermous Flora must take cognisance of the fact 

 that no trace of a glacial period has been discovered in South Africa 

 later than Permian times. Moreover, geological evidence is strongly 

 in favour of the assumption that South Africa never reached much 

 further southwards than it does now. It is inconceivable that in a 

 shifting of localities such as a glacial period would involve, two such 

 highly specialised and large conglomerates of species of the most 

 diverse orders such as we find in the Cape Province and the Central 

 Districts of Cape Colony could have persisted, and there is no reason 

 to think that the extreme differentiation of plants found in South 

 Africa could have been accomplished since the last period of glacia- 



