V FOOD OF LARGF QUADRUPEDS 89 



the elevation of the land has been small (without there has 

 been an intercalated period of subsidence, of which we have no 

 evidence) since the great quadrupeds wandered over the sur- 

 rounding plains ; and the external features of the country must 

 then have been very nearly the same as now. What, it may 

 naturally be asked, was the character of the vegetation at that 

 period ; was the country as wretchedly sterile as it now is? 

 As so many of the co-embedded shells are the same with those 

 now living in the bay, I was at first inclined to think that the 

 former vegetation was probably similar to the existing one ; but 

 this would have been an erroneous inference, for some of these 

 same shells live on the luxuriant coast of Brazil ; and generally, 

 the characters of the inhabitants of the sea are useless as guides 

 to judge of those on the land. Nevertheless, from the following 

 considerations, I do not believe that the simple fact of many 

 gigantic quadrupeds having lived on the plains round Bahia 

 Blanca, is any sure guide that they formerly were clothed with 

 a luxuriant vegetation : I have no doubt that the sterile country 

 a little southward, near the Rio Negro, with its scattered thorny 

 trees, would support many and large quadrupeds. 



That larg^nimals require a luxuriant vegetation, has been 

 a general assumption which has passed from one work to 

 another ; but I do not hesitate to say that it is completely false, 

 and that it has vitiated the reasoning of geologists on some 

 points of great interest in the ancient history of the world. 

 The prejudice has probably been derived from India, and the 

 Indian islands, where troops of elephants, noble forests, and im- 

 penetrable jungles, are associated together in every one's mind. 

 If, however, we refer to any work of travels through the southern 

 parts of Africa, we shall find allusions in almost every page 

 either to the desert character of the country, or to the 

 numbers of large animals inhabiting it. The same thing is 

 rendered evident by the many engravings which have been 

 published of various parts of the ihterior. When the Beagle 

 was at Cape Town, I made an excursion of some days' length 

 into the country, which at least was sufficient to render that 

 which I had read more fully intelligible. 



Dr. Andrew Smith, who, at the head of his adventurous 

 party, has lately succeeded in passing the Tropic of Capricorn, 



