A NATURALIST IN BRAZIL 



their individual numbers are so great that they are the animals most 

 frequently encountered in any part of the world, and form the most 

 important and unfailing item of the diet of almost all birds and 

 beasts of prey. 



When the Rodents made their way into South America they found 

 an almost virgin country. The grasses were as yet almost untouched, 

 so that the Rodents, herbivorous from of old, were able to adapt 

 themselves to this form of nourishment in a great variety of ways. 

 There were, of course, in the South America of the older Tertiary 

 period, great herbivores like our Ungulates; for example, the 

 Toxodon, a sort of three-toed hippopotamus, and the Macrauchenia, 

 which reminds one of the Llama, but which also had three toes ; 

 and one may see the complete skeletons of these two animals in the 

 La Plata museum. But remains have been found of yet other species 

 which differ so greatly from our Ungulates — whether single-hoofed 

 or cloven-hoofed — that special orders have been established for 

 them. Among them was the Tapir or Anta, of which I have already 

 spoken. 



But these animals, these primitive Ungulates, were apparently 

 not very numerous, and their types, of which they were, so to speak, 

 the forerunners, were not as yet firmly established, so that the 

 Rodents, with their great fertility, were able to push in among 

 them, and even to begin to supplant them. For a very characteristic 

 South American group is that of the Caviidae, in which the nails 

 of the toes have to some extent assumed the form of a hoof, while 

 the balls of the toes are covered with horny callosities. These 

 creatures, therefore, have undergone a development similar to that 

 of the Ungulates, whom they resemble in respect of their nourish- 

 ment and their rapid gait ; and in size they exceed most of their 

 relatives in other parts of the world. 



Beside the Brazilian rivers lives the Capyvara, the "Lord of the 

 Grass," as the old Indian name of Capi-i-uara means, according to 

 Goeldi. This portly creature, about the size of a yearling pig, with 

 a coat of long yellowish-brown hair, attempts, as far as it can, to 

 follow the example of the Hippopotamus. If startled, it rushes into 

 the water with a loud cry of warning. On bright moonlit nights, 

 where the riverside forest opens to leave a grassy glade, the Capyvara 

 may be seen grazing, or sitting up on his hindquarters like a dog 



(Fig. 33)- 



Another aquatic animal is the Nutria or Swamp-beaver, which, 

 as its name tells us, resembles in appearance the Beaver of the 

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