Basin- like Form of Africa. 53 



has at length traced the different formations, and delineated 

 them on the above-mentioned map. In this way he has 

 shewn us that the oldest rocks (whether crystalline gneiss or 

 clay-slate, here and there penetrated by granite) form a 

 broken coast fringe around the colony, from the southern to 

 its western and eastern shores, and are surmounted by sand- 

 stones which, from the fossils they contain, are the equiva- 

 lents of the Silurian or oldest fossil-bearing rocks.* These 

 primeval strata, occupying the higher grounds, of which the 

 Table Mountain is an example, and dipping inland from all 

 sides, are overlaid by carboniferous strata, in which, if no 

 good coal has yet been found, it is clear that its true place 

 is ascertained ; and as Mr Bain has detected many species 

 of fossil plants of that age, we may still find the mineral 

 pabulum for the steamers which frequent these coasts. 



Above all these ancient strata, and occupying, therefore, 

 a great central trough or basin, strata occur which are 

 rentarkable from being charged with terrestrial and fresh- 

 water remains only ; and it is in a portion of this great ac- 

 cumulation that Mr Bain disinterred fossil bones of most 

 peculiar quadrupeds. One of the types of these, which Pro- 

 fessor Owen named Bicynodon from its bidental upper jaw, 

 is a representative, during a remote secondary period, of the 

 lacertine associates of the hippopotami of the present lakes 

 and waters. The contemplation of this map has, therefore, 

 led me to point out to you how wide is the field of thought 

 which the labours of one hard-working geologist have given 

 rise to, and to express, on my part, how truly we ought to 

 recognise the merits of the pioneer among the rocks, who 

 enables us, however inadequately, to speculate upon the 

 entirely new and grand geographical phenomenon, that such 

 as South Africa is now, such have been her main features 

 during countless past ages, anterior to the creation of the 

 human race. For the old rocks which form her outer fringe, 

 unquestionably circled round an interior marshy or lacustrine 

 country, in which the Dicynodon flourished at a time, when 



Mr Bain himself so styles these rocks in the Map deposited in the Library 

 of the Geological Society. 



