Chestnut- Faced Pocket Gopher 91 
more injurious to man than either of our others, as the 
mounds of earth thrown up by it are much larger than those 
of any of the other gophers, and it naturally requires more 
FIG. 31. CHESTNUT-FACED POCKET GOPHER, Cratogeomys castauops 
Skull showing dentition x if 
food. A female, taken in Baca County May 21st, contained 
three embryos, but half-grown young had been taken a 
month earlier than that, and also nursing females. 
Family MURID^ 
Animals mostly of terrestrial habits, and usually of small 
or moderate size, with naked and scaly or but scantily haired 
tails and a rudimentary poUex; skull without postorbital 
processes and with contracted frontals; the anterior portion 
of the zygomatic arch is usually flattened into a perpen- 
dicular plate so that the infraorbital foramen forms a 
somewhat T-shaped opening when viewed from above; 
