Floioering Plants and Ferns of the Cape Peninsula. 229 



occur in any other countries ; yet they have no single species and 

 only two or three genera, in common, out of many. . . . Diosmese, 

 a large tribe of EuTACEiE abundant in this Eegion, find a counterpart 

 in Australia in the tribe Boronieae of the same Order. The tribe 

 Ericeae, of the Order Ericaceae, has over 400 species in this Eegion 

 alone ; not one occurs in Australia, but the place of the tribe is 

 taken by the large Order EpACRiDACEiE, very closely allied to it, and 

 which is almost confined to Australasia." '•' There is no genus of 

 EuTACE^ or Proteace^, and only three of Eestionace^, common 

 to both Eegions. In Composit.e, Bentham has pointed out several 

 identical genera which are abundant in South Africa, notably 

 Heliptermn with 12 South African and 30 Australian species, and 

 Heliclirysum with 137 and 52 species respectively. 



" The following Orders, characteristic of Australian vegetation, 

 abound most, after Australia, in South Africa: THYMELiEACEiE, 

 H^MODORACE^, Droserace^ ; and another point of approach is 

 found in the remarkable deficiency in both countries of the widely- 

 diffused Orders Eubiace^, Laurace^, and Arace^." 



There are certainly some remarkable divergences, of Orders rare 

 or absent in either country and represented in the other, which 

 Hooker has specified in detail. To these may be added that whereas 

 in the Orchidace^ of Australia it is the tribes Vandeae and Neottiese 

 which most largely prevail (Ophrydeae being restricted to two 

 species), in our Peninsular Flora the Vandeae are few, the Neottieae 

 absent, while Ophrydeae abound. Still, these divergences do not 

 destroy the striking significance of the affinities before mentioned. 



Sir J. Hooker conjectures the probability of a common origin of the 

 Australian and South African {i.e., the South-west African) Floras, 

 derived from ancestors inhabiting a vast antarctic continent of which 

 the greater part has been submerged ; and that during the ages 

 which have succeeded the severance of the continents the two Floras 

 have become differentiated as we now know them. I The evidence, 

 it should be added, is not merely South African, but is corroborated 

 by the spread of some of the Australian Orders mentioned above 

 (Epacridace^, Proteace^, Eestionace^) northward towards 



* This and the following quotations are taken, for the sake of brevity, from my 

 " Sketch of the Flora of South Africa" in the Official Handbook of the Cape of 

 Good Hope, 188G ; the substance being derived from Hooker's Essay, above-men- 

 tioned. 



t More recent discoveries have tended, as far as they go, to support this 

 hypothesis : the presence, on the mountain-tops of South-west Africa, of 

 NiDiolirion, a small Liliacea, a close ally of Herpolinon, found in similiar stations 

 in S.E. Australia ; and the facts and conclusions adduced in Mr. Clarke's paper 

 on the Antarctic Origin of the tribe Schamese, cited above. 



