268 Mr. J. P. M. Weale on the variation of 



some districts, differs in growth and in the number of 

 prickles in some localities, and is said to have assumed 

 distinct varieties, being sometimes almost free from 

 prickles, and called bj the farmers the Kaalblad, or naked 

 leaf. 



I believe that more extensive researches will show that 

 the whole of the south-eastern seaboard is gradually being 

 upraised (a conclusion already confirmed by some South 

 African geologists), and that this upheaval has been ac- 

 companied on the seaboard by a moister climate suitable 

 to the immigrant flora and insect fauna of sub-tropical 

 South Africa. Hence it is that the few existing arboreal 

 forms of plants are only to be found in the patches of 

 forest clothing, the southward aspect of the mountains, 

 and the intervenins; tracts between them and the Indian 

 Ocean. 



In the deeper valleys, which represent the river beds 

 of this tract, the plants show distinct relationships to 

 those of the interior plains; in some instances, this is 

 doubtless due to the transportation of seeds during floods, 

 and partially to the great heat and aridity of these low- 

 lying lands; but these conditions are absent in several 

 cases where the rivers have very short courses, and there- 

 fore the affinity of these local floras appears to me to 

 point out that they are survivals of the original inland 

 flora, whose area has been gradually contracted. 



So far as man is concerned, there can be little doubt 

 that ih^Abantu, or dark-coloured races (known commonly 

 as Kafir and Fingo) have driven the lighter races, or 

 Koi-koin (Hottentots and Bushmen) to the south, and 

 curiously enough the traces of these last for the most part 

 survive only in the names of the rivers, most of which are 

 still known by Bushman names. 



The Kafir tribes, too, being dependent on cattle and 

 sorghum for their sustenance, naturally avoided the in- 

 terior plains, and some of them show very distinctly the 

 fusion of the two races, not merely in their features, but 

 also in their language. 



Without these preliminary remarks, it appears to me 

 difficult to understand the distribution and variation of 

 South African insect forms. 



The great similarity of conditions (omitting those dis- 

 tinctions already alluded to) ; the absence of any large 

 rivers or of very lofty mountain chains (the average 

 height being less than 4,000 feet) ; of deep inlets of the 



