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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 much less size, 
have been found in North America, and described by Mr. Jefferson. 
Furnished with the necessary knowledge by the anatomical exa- 
minations referred to in the preceding part of this letter, and assisted 
by plaster 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 (Brady pus) 
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 un- 
gual bone, has in its middle a well marked ridge, which considerably 
straightens the ginglimus with the adjoining bone. This is in perfect 
agreement 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 convex part downwards, as in the sloths and 
ant-eaters. From these, and indeed other concurrent circumstances, 
it seems to be fair to conclude 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 
