346 Transactions of the South African Philosophical Society. 



South- Western Cape Colony) allied to Bencoma (a genus with 2 

 species on Madeira and the Canary Islands). 



A former northward extension of the typical Cape Flora can 

 scarcely be denied if our views are correct, for at the time when the 

 Uitenhage beds were laid down, the central portions of Cape Colony 

 must to a large extent have stood in the same relation to the 

 continent as the present coast districts. Whether the occurrence 

 of species of Glijfortia and a Bestio on the Eoggeveld can be used 

 as evidence of such former extension seems to me, however,, 

 doubtful. 



A former eastward extension is certainly demanded by our theory. 

 The data for an exact statement of the relations of the Southern 

 Coast Flora as far as Natal with the Flora of South- West Cape 

 Colony are scarcely worked out sufficiently, but we know that even 

 now many outliers of the typical Cape Flora reach far east, and 

 their number would probably be much greater if the Tropical 

 African Flora did not appear as a formidable competitor in the 

 Coast Eegion where summer rains become more and more prevalent. 

 The mean annual temperature increases as we go further and 

 further north-east, and though we cannot speak very decidedly on 

 this point, it seems to me that owing to the lowering of the 

 mountains since Upper Cretaceous times and the alternate sub- 

 sidence and elevation of the coast-lands of which we have already a^ 

 fair amount of knowledge, the Tropical African Flora has had a 

 good chance of supplanting the typical South-West Flora along th& 

 outh coast of Cape Colony to a very large extent. 



Marloth (1905, p. 589) recognises besides his " Cape Province '" 

 only a " Palseotropical Province." There is undoubtedly a good 

 deal to be said for this division of the South African Flora, but 



1 think it would have been wiser to place the "Karroo" into a 

 phyto-geographical province by itself, although it stretches its arms 

 like a big octopus into the neighbouring regions wherever suitable 

 conditions exist. Some of the types characteristic of this region 

 show still relations to the Flora of Australia while others show 

 relations to the Tropical Floras of both hemispheres as seen by 

 the subjoined distribution of AizoacecB and PhytolaccacecB (as defined 

 by Pax in Engler-Prantl, iii., 1^). 



AlZOACEiE. 



I. Molhiginoiclece. 



2 genera in the Tropics of both hemispheres, 3 {Pliarnacium, Hyper- 

 stelis, and CoelantJrnm) restricted to South Africa, 1 in New South. 



