FAUNA AMERICANA. 171 



white, with chisel shaped cutting edges, wearing 

 away, and frequently channelled inside, those in 

 the upper jaw short and somewhat truncated ; 

 lower one-third longer, rather narrower, and ter- 

 minated by nearly a semicircular outline; molars 

 five above and four below, posterior largest; some 

 adults with only four above, their crowns are 

 bounded by an irregular bending plate of enamel, 

 intersected by two transverse ridges of unequal 

 height, and presenting a few obtuse points; back 

 covered with soft fur, consisting of a soft down of 

 a dark smoke-gray at the roots, pale fresh-gray in 

 the middle, and yellow-gray at tips ; this arrange- 

 ment produces a crowded assemblage of ill de- 

 fined irregular and confluent whitish spots, mar- 

 gined and separated by black and yellowish-gray; 

 these spots assume a transverse arrangement on 

 the posterior part of the back; throat and all un- 

 derneath brownish-red and brownish-yellow, or 

 rather a colour intermediate ; colours of the back 

 and belly run into each other. Tail flattish and 

 subdistichous, the hairs of which the animal is 

 capable of expanding like a feather, in which state 

 the tail is brown along the middle, tipped and 

 margined for two-thirds of its length with black; 

 feet with short depressed claws, large, biackish^ 

 slightly arched, and grooved underneath ; on the 

 inside of the fore feet, and high up, there is a 

 email toe or thumb armed with a small nail; 

 palms naked and with callous protuberances^ 



