io6 Report S.A.A. Advancement of Science. 



in South Africa have been there most likely from Cretaceous times. 

 In the Northern Hemisphere, and also in Australia, angiospermous 

 plants have been discovered in lower Cretaceous strata. We know 

 for a fact that the period of the drying up of the huge lakes which 

 occupied the interior of South Africa during Triassic times, coin- 

 cides with a remarkable development of the higher animals in South 

 Africa, and it seems reasonable to conclude that a corresponding 

 development must also have taken place in the vegetable kingdom. 

 If it is objected that we find no fossil evidence for this statement, I 

 may point out that even in Europe and other well explored parts of 

 the world, we only know well preserved remains of forest plants in 

 Cretaceous and Tertiary deposits, chiefly trees and shrubs. We 

 scarcely know any remains of plants from the undergrowth of 

 forests, and scarcely any from treeless and shrubless formations, and 

 yet these must have always existed. The absence of palgeontological 

 evidence for our hypothesis is therefore not quite so serious as appears 

 at first sight. 



The present composition of the angiospermous Flora of South 

 Africa points clearly to the conclusion that it is of extreme anti- 

 quity. In South-Western Cape Colony especially we find a large 

 number of isolated types, a considerable number of endemic 

 genera, huge numbers of endemic species, and even a few endemic 

 natural orders. We find, further, in the Karroo districts, another 

 highly specialised flora which is adapted to certain extreme conditions 

 of climate. We can even find traces of such high specialisation further 

 north, at all events as far north as the Cunene River. We have, 

 therefore, the curious phenomenon that the South Western Flora is, 

 as it were, boxed up in a comparatively limited area, beyond which 

 escape is practically impossible northwards as the conditions in this 

 direction are adverse to it. As these conditions must have existed 

 for an immense period of time, it seems quite out of the question 

 that this peculiar flora should have been derived from a northern 

 scource. Now it is a further curious fact, which has been insisted 

 upon ever since Hooker published the essay previously referred to, 

 that a great many of these types find their chief development in 

 South Africa and Australia. Consequently a common origin of 

 many important constituents of the floras of these two countries has 

 been stipulated by many authors. Some of these types, such as 

 Proteacese, were supposed to have originated in the Northern Hemi- 

 sphere, but the most competent authorities have declared the evidence 

 on which this conclusion was based to the worthless, and the convic- 

 tion is more and more gaining ground that not only the Proteacese, 

 but a great many other angiospermous plants have had their origin 

 in the Southern Hemisphere. Hooker had already pointed out that 

 the many bonds of afilnity between the Southern floras, namely, 

 the Antarctic, Australian, and South African floras, indicate that 

 these rnay all have been members of one great vegetation, which may 

 once have covered a southern area as large as the European Flora does 

 in the north. However, he in no way commits himself to the statement 



