New Murine Rodents from Mexico. 129 



Neotomodon perotensis sp. nov. 



Type from Cofre de Perote, Vera Cruz, Mexico (alt. 9500 ft.). No. 

 54398, $ ad., U. S. Nat. Mus., Biological Survey Coll. Collected May 

 29, 1893, by E. W. Nelson. Orig. No. 4897. 



Characters. Similar to N. alstonl, but ears and tail shorter; color paler, 

 with a distinct blackish dorsal stripe in summer pelage. 



Color. Upper parts in fresh summer pelage (end of May) grayish buff, 

 grayest on head, buffy on sides, with a distinct (but not sharply limited) 

 blackish band on back ; under parts white, suffused with buffy on pec 

 toral region, and with the plumbeous basal fur slightly showing through ; 

 wrists and ankles dusky; fore and hind feet white; tail sharply bicolor, 

 dusky above, white below. Specimens in left-over winter pelage are 

 much darker and resemble N. alstoni. 



Cranial characters. Skull similar to that of N. alstoni, but slightly 

 smaller, and in old age not becoming so angular. 



Measurements. Type specimen : Total length 212 ; tail vertebrae 91 ; 

 hind foot 24. Average of 4 specimens from type locality : Total length 

 213 ; tail vertebrae 92.5 ; hind foot 25. 



Neotomodon orizabae sp. nov. 



Type from Mt. Orizaba, Puebla, Mexico (alt. 9500 ft.). No. 53486, tf 

 old, U. S. Nat. Mus., Biological Survey Coll. Collected April 26, 1893, 

 by E. W. Nelson. Orig. No. 4747. 



Characters. Similar to N. alstoni and perotensis, but much smaller and 

 grayer, with slightly smaller ears and decidedly shorter tail. Resembles 

 a gray Microtus. 



Color. Upper parts uniform buffy-gray ; under parts white, suffused 

 with buffy on pectoral region, with plumbeous basal fur showing through ; 

 wrists and ankles dusky ; fore and hind feet whitish ; tail sharply bicolor, 

 brownish above, white below. 



Cranial characters.- Skull like that of perotensis, but smaller and weaker. 



Measurements. Type specimen: Total length 194; tail vertebrae 81; 

 hind foot 24. Average of 4 specimens from type locality : Total length 

 194 ; tail vertebrae 82 ; hind foot 25. 



