130 Annals of the Soutli African Museum. 



modified by incursions from the Western Karroo and the Upper 

 Eegion. The Khamiesberg, on the other hand, has no direct union 

 with the Cape System — from which it is separated by the barren 

 Knechtsvlakte — and its connection with the eastern tableland is by 

 way of Bushmanland and the Upper Eegion. 



In the Bokkeveld, the Matsiekamma and the Oliphant's River 

 Mountains, the main outcrop is Table Mountain sandstone. There- 

 fore both climatic and edaphic conditions in general favour the 

 development of the Cape flora. The structure of the Khamiesberg, 

 however, is very different and is less well known. I am indebted 

 to my friend Dr. A. W. Rogers, F.G.S., for the following note on 

 its geology : — 



" The Khamiesbergen are made of gneiss, with quite subordinate 

 masses of schists and granitites representing sedimentary and 

 volcanic rocks in a highly altered condition. The general trend of 

 the foliation and schistose structures is from east to west. These 

 very ancient (archean) rocks have long been stripped of sediments 

 of later date (Nama formation and the Karroo beds) which probably 

 covered them formerly. It is quite uncertain whether the Cape 

 formation also extended as far north-west as the Khamiesbergen. 

 From a physical point of view, the region is a westerly extension of 

 the Bushmanland plateau, deeply cut into by the streams which 

 flow directly into the Atlantic or join the Buffels and Oliphant's 

 Rivers." 



The occurrence of a pronounced element of Cape affinity at higher 

 elevations in the Khamiesberg is therefore a matter of some 

 geographical interest. It is even more remarkable than the presence 

 of characteristic Cape genera on the Huilla plateau in South Angola ; 

 for the latter locality is geologically much more nearly allied to the 

 mountains of the Cape System and its rainfall is probably much 

 greater. 



The distribution of the collecting parties was as follows : Miss R. 

 Glover and Miss E. L. Stephens worked in the valley of the 

 Oliphant's River in the vicinity of the Warm Baths springs. Mr. 

 E. P. Phillips encamped and collected on the flat summit of the 

 Matsiekamma. The writer crossed the Knechtsvlakte to the north 

 of Van Rhynsdorp and visited various localities in the Khamies- 

 berg, between 2,000 and 6,000 ft. 



In this, as in the previously issued part, many of the deter- 

 minations could not have been made in South Africa without the 

 kind co-operation of the Director and Staff of the Royal Botanic 

 Gardens, Kew, which I gratefully acknowledge. In the study of 



