220 MAMMALS. 



we have animals feeding upon three kinds of food, — the Ant-eaters feeding upon ants and other 

 insects, as their name declares ; the Armadillos, omnivorous, feeding on almost anything, — fruit, 

 leaves, roots, insects, flesh, and having no prejudices against off;il ; and the Megatheroids and 

 Sloths, whose sustenance was and is wholly vegetable. For each of these kinds of diet the animal 

 has a special organization, and the mode of procuring it is quite a minor consideration. If it does 

 so by burrowing or by climbing trees or by walking on the ground, its limbs will be modified to 

 suit that mode of getting at its food ; but the main organs will remain untouched. They are 

 essential : the others accidental. For this reason I prefer Owen's division, in which he places 

 the Megatheroid animals and the Sloths in the same section. It may be right to divide that 

 section into the large extinct burrowing species and the small existing arboreal animals ; the ac- 

 cident of their getting the same food in different ways, as well as their difference in size, 

 (for, as already said, size is an element in the affinities of nature,) justify this ; but it is a divi- 

 sion of different value and less importance than that between the other groups of the family. 



For the same reason I think that Giebel has made a mistake in carrying tlie_0RYCTER0Pus from 

 the Ant-eaters to the Armadillos. He has doubtless placed it among the Fodientia or Burrowers, 

 because it burrows ; but its true affinities are with the Versiilinguia. The form of the tongue in 

 the Monotremata, the Myrmecobius, and MyrmecojAaga, is a long, round thing, like an earth- 

 worm, and that of the Orycteropus is of the same type, long, thin, but flat, like a piece of tape ; 

 their j)urpose is the same, although their mode of application is slightly diflerent. The general 

 structure of the animals is, moreover, essentially the same, and their geographical distribution 

 may be interpreted in accordance with their affinity. 



In compliment to our latest acquaintances, the Whales and the Pachyderms, I shall commence 

 with the largest, — the Sloths and Megatheroid animals. 



I. Bradypodid^. (1). Gravigrada. The Megatheroid animals are now all extinct. In 

 South America their remains have been found in Brazil, in Paraguay, in Uruguay, near Buenos 

 Ayres, in North Patagonia, and on the other side of the Andes at Lima. Agassiz proposed to divide 

 this group into two sections, of which the Megatherium and Megalonyx were the types ; but, as 

 his distinction was mainly founded on the idea that the one (the Megathere) had a long trunk, 

 and the other, the Megalonyx, a short snout, an assumption which, as regards the Megathere, turns 

 out to be untenable, I do not adopt it.* 



A species of Megatherium, not the South American M. Cuvieri, but an allied one, M. 

 jiiRABiLE, formerly inhabited Georgia and South. Carolina, but traces of it have not been found 

 further to the north. Remains of a species of Mylodon different from that of South America, occur 

 through a great part of North America, from Natchez on the Mississippi to Big-bone Lick, in 

 Kentucky, in the east, and to the Williamette River, in Oregon (one of the tributaries of the 

 Columbia), on the west. One sj)ecies of Megalonyx lived in North America f whose remains 

 have been found in caves in Tennessee, and in deposits at Natchez, and in Virginia. Bones of the 

 Ereptodon priscus have been found in the deposits through which the Mississippi runs. 



* Agassiz in "Boston Soc. Nat. Hist." Sept. 1862, North and South America, and of the interior of the 



p. 102. United States, it is not a little remarkable tliat neither in 



t Ur. Falconer, in his paper on " Fossil Elephants," al- the lower mioeeue of the Nebraska, nor in the pliocene 

 ready so often quoted, says, " Knowing as we do, what au fauna of Niobrara, both of which have been so ably in- 

 important feature the lai'ge extinct Edentata constitute vestigated by Leidy, has a single edentate form been dis- 

 in the newer pliocene fauna of the littoral regions, both of covered." — Nat. Hist. Rev. iii. p. 62. 



