332 



GENUS PSEUDOSTOMA.— Sat. 



DENTAL FORMULA. 



Incisive ■= ; Canine r^ ; Molar -— = 20. 



2 — 4 — 4 



Incisors, naked, truncated ; molars, destitute of radicles ; crowns, 

 simple, oval ; anterior ones, double. 



Head, large and depressed ; nose, short ; mouth, small. 



The cheek-pouches are large, and open exterior to the mouth. 



The eyes are small and far apart. The external ear is very short ; 

 auditory openings, large. Body, sub-cylindrical ; tail, rather short, round, 

 tapering slightly, clothed with short hairs. 



Legs, short, with five toes to each foot. 



Burrowing in sandy soils, feeding on grasses, roots, nuts, &.C., which 

 they convey to their burrows in their capacious cheek-pouches, are habits 

 common to this genus. 



There are about six well determined species of Pouched Rats, all ex- 

 isting in North America. 



The generic name is derived from -j/ivSa^ {pseudo,) false, and trrcfue, 

 {stoma,) a mouth, in illusion to the false mouths or cheek-pouches of the 

 genus. 



PSEUDOSTOMA BURSARIUS.— Shaw. 



Canada Pottcbed Rat. 

 PLATE XLIV — Males, Female aitd Youmg. Natural size. 

 P. supra, rufo-fuscus ; subtns, cinereo-fuscus ; pedibus, albis. 



CHARACTERS. 



Reddish-brown above, ashy-brown beneath ; feet, white. 



