SIGMODON. 231 



Color. Above yellowish gray, tinged about ears, face, and rump 

 with ochraceous; nose, orbital ring, and base of tail bright ochraceous; 

 beneath white; hands and feet buffy gray; tail above blackish, 

 beneath buffy gray. 



Measurements. Total length, 260; tail, 117; hind foot, 29. 

 Skull of type: basal length, 28; nasals, n.6; zygomatic breadth, 19; 

 mastoid breadth, 13; alveolar length of upper molar series, 5.5. 

 (Bailey, 1. c.) 



205. alticola (Sigmodon), Bailey, Proc. Biol. Soc. Wash., xv, 1902, 



p. 116. 

 ALPINE COTTON RAT. 



Type locality. Cerro San Felipe, State of Oaxaca, Mexico. 

 Altitude, 10,000 feet. 



Geogr. Distr. Mountains of State of Oaxaca, Mexico. 



Genl. Char. Size medium; tail hairy; pelage long and soft. 

 Skull : similar to that of 5. leucotis ; lateral pits of palate very shallow. 



Color. Above dark ochraceous or light umber brown; beneath 

 pale cinnamon brown; hands and feet yellowish gray; tail black, 

 yellowish brown at base beneath; ears gray. 



Measurements., Total length, 230; tail, 101; hind foot, 28.5. 

 Skull of type: basal length, 28.5; nasals, n; zygomatic breadth, 17.8; 

 mastoid breadth, 13.5; alveolar length of upper molar series, 6.3. 

 (Bailey, 1. c.) 



a. amoles (Sigmodon), Bailey, Proc. Biol. Soc. Wash., xv, 1902, 



p. 116. 

 AMOLES COTTON RAT. 



Type locality. Final de Amoles, State of Queretaro, Mexico. 



Geogr. Distr. Known only from type locality. 



Genl. Char. Similar to 5. alticola. Skull wider, smaller bullae, 

 and lateral pits of palate deeper, and interparietal without median 

 division. 



Color. Like 5. alticola, but upper parts duller and less tawny. 



Measurements. Total length, 252; tail vertebrae, 105; hind foot, 

 29.5. Skull of type: basal length, 29.5; nasals, 5.7; zygomatic 

 breadth, 19.6; mastoid breadth, 14; alveolar length of upper molar 

 series, 6.3. (Bailey, 1. c.) 



206. austerulus (Sigmodon), Bangs, Bull. Mus. Comp. Zool., xxxix, 



1902, p. 32. 

 VOLCAN DE CHIRIQUI COTTON RAT. 



Type locality. Volcan de Chiriqui, Chiriqui, Panama. Altitude, 

 10,000 feet. 



