403 



LETTER XXIX. 



FOSSIL REMAINS OF ANIMALS OF THE ORDER BRUTA, OF LINN.51US; 

 TARDIGRADI, OF DUMERIL MEGATHERIUM MEGALONIX. 



1 HE sloths, of which there are but two species, the Ai, Bradypus tri- 

 dactylus ; and the Unau, Eradypus didactylus ; form the only genus which 

 M. Dumeril has placed in the family of Tardigradi. Linnaeus has dis- 

 posed these animals under the genus Bradypus, in the order Bruta. The 

 fossil remains which are here to be noticed will be found to approximate 

 not only to these animals, but also to the ant-eaters, the next genus, 

 Myrmecophaga, in the order Bruta, of Linnaeus; and the first in the 

 family of Edentuli, of Dumeril. 



The osteology of the sloth is particularly interesting, not merely from 

 the explanation it affords of the singular circumstances resulting from 

 the economy of these animals, but also from the information which it 

 enables us to obtain respecting the nature of the Megatherium of Para- 

 guay, and of the Megalonir of Virginia. Influenced by these considera- 

 tions, Cuvier availed himself of the opportunities of examination which 

 he possessed, and published an account of the observations which he 

 thus made. Ann du Mus. Toniev. p. 189. 



Of the sloths, he observes : We find in them so little agreement with 

 ordinary animals the general laws of organized bodies at present exist- 

 ing apply so little to them the different parts of their bodies seem to be 

 so much in contradiction to the rules of co-existence which we find esta- 



