CRATOGEOMYS. 313 



b. No sagitt&l crest. 



a/ Outer face of upper incisor strongly bev- PAGE 



eled C. oreocetes 314 



b/ Outer face of upper incisor not beveled . . . . C. peregrinus 314 

 B. Basioccipital rectangular, its sides parallel. 



a. Rostrum and braincase long C. castanops 315 



b. Rostrum short, braincase broad C.c. goldmani 316 



309. merriami (Geomys}, Thomas, Ann. Mag. Nat. Hist., 6th Ser., 



xn, 1893, p. 271, pis. and figs. 

 MERRIAM'S POCKET GOPHER. 



Type locality. "Southern Mexico." 



Geogr. Distr. Valley of Mexico and Toluca Valley, State of 

 Mexico, and States of Puebla and Hidalgo. "South end of Valley 

 of Mexico to an altitude of 10,000 or 11,000 feet; east to Atlixco, 

 State of Puebla, north to Irolo, State of Hidalgo, and west to Ler- 

 main, Toluca Valley." (Merr.) 



Genl. Char. Size large; tail moderately haired. Skull massive; 

 incisors very large; outer edge of enamel on lower incisors forming 

 a bead; squamosals covering parietals and meeting in a median crest. 



Color. Upper parts varying from mixed chestnut brown and 

 black to slate black (melanistic) ; under parts paler; dusky patch 

 around and behind ears. 



Measurements. Total length, 380; tail vertebrae, 112; hind foot, 

 50. Skull: basal length, 51-70.5 ; Hensel, 46.5-64; zygomatic breadth, 

 35-49; interorbital width, 7.5-9.5; length of upper molar series, 

 11.5-15.5; length of single half of mandible, 36.5-52. 



310. perotensis (Cratogeomys}, Merr'., Mon. Geomyidae, N. Am. 



Faun., No. 8, 1895, P- J 54> pi- 8, fig- 6. 

 PEROTE POCKET GOPHER. 



Type locality. Cofre de Perote, State of Vera Cruz, Mexico. 

 Altitude, 9,500 to 12,000 feet. 



Geogr. Distr. State of Vera Cruz, Mexico. 



Genl. Char. Size smaller than C. merriami; hind feet and tail 

 hairy; no naked nose pad. 



Color. Upper parts mixed fulvous and black; usually a white 

 patch at base of tail ; dusky patch behind ear ; under parts plumbeous 

 washed with fulvous; hind feet white basally, usually dark for remain- 

 ing portion, sometimes all white; tail dusky and white. 



Measurements. Total length, 300; tail vertebrae, 79; hind foot, 

 40. Skull: basal length, 51.5-55; Hensel, 47-51; zygomatic breadth, 

 37-39.5; interorbital width, 7-7.5; length of upper molar series, 

 10.5-12; length of mandible, 37.5-40.5. 



