408 



Faujas St. Fond, speaking of the megatherium, refers these bones, 

 found at Virginia, to a similar animal, differing only in size, saying that 

 the remains of animals of the same species, but of a much less size, have 

 been found in North America, and described by Mr. Jefferson. 



Furnished with the necessary knowledge by the anatomical examina- 

 tions referred to in the preceding part of this letter, and assisted by plas- 

 ter casts of the American bones, described by Mr. Jefferson, and by two 

 bones, and particularly by a tooth, with the examination of which he was 

 favoured by M. Palisat de Beauvois, who had obtained them from the 

 same cavern which had supplied those described by Mr. Jefferson, 

 M. Cuvier was enabled to determine that these fossil bones were the 

 remains of an animal of a species of sloth (Bradypus) hitherto unknown. 



Their agreement with the bones of the sloth, or of the neighbouring 

 genus the ant-eater, appears to be confirmed by the following charac- 

 teristic circumstances. The articular face of the last phalanx, or ungual 

 bone, has in its middle a well marked ridge, which considerably straight- 

 ens the ginglimus with the adjoining bone. 'This is in perfect agree- 

 ment with what occurs in the sloths and the ant-eaters ; whilst, in the 

 animals of the genus fells, or cat kind, the joints of the toes are more 

 free, and this ridge is nearly effaced. 



The upper part of this surface is prolonged farther backward than the 

 lower ; hence, the last bone could only be extended in a right line : it 

 consequently could not be turned backwards with its point upwards, as 

 in the cat kind; but might have been bent entirely underneath, with its 

 cpnvex part downwards, as in the sloths and ant-eaters. From these, 

 and indeed other concurrent circumstances, it seems to be fair to con- 

 clude that this ungual bone was that of a sloth ; but two other ungual 

 bones, probably of the same foot, were found to differ in size from the 

 former bone, as well as from each other. In this they differ both from 

 the sloths and the cat kind, which have their nails nearly equal, and 

 agree with the ant-eaters, in which the nails are very unequal. In the 

 other bones of this finger, a perfect accordance is observable; and still 



