PEROMYSCUS. 199 



Geogr. Distr. State of Sonora, Mexico; extent of range unknown. 



Genl. Char. Similar in color to P. eremicus; soles bare; ears 

 naked ; tail long and scantily haired. 



Color. Above pale yellowish gray mixed with black; cheeks, 

 outer side of arms, and sides pale fulvous or cinnamon; under 

 parts white with buff spot on chest ; hands and feet white ; tail above 

 little darker than back, beneath paler. 



Measurements. Total length, 217 ; tail vertebrae, 113; hind foot, 23. 



167. hemionotis (Peromyscus) , Elliot, Pub. Field Columb. Mus., in, 



1903, p. 157. Zoology. 

 MULE-EARED MOUSE. 



Type locality. Rosarito Divide, San Pedro Martir Mountains, 

 Lower California, Mexico. 



Genl. Char. Similar in color to P. stephcnsi; ears enormous; tail 

 very long. 



Color. Nose and tufts in front of ears dark gray; top of head 

 and upper parts cream buff finely lined with black ; bright ochraceous 

 lateral line from lips to root of tail; under parts pure white, base of 

 hairs plumbeous showing through; hands and feet white; tail above 

 brownish black, beneath white; ears dark brown. 



Measurements. Total length, 222; tail vertebrae, 126; hind foot, 

 22.5; ear, 25.5. Skull: occipito-nasal length, 27; Hensel, 20.3; zygo- 

 matic width, 13; interorbital constriction, 4.5; breadth of braincase, 

 13; palatal arch to alveoli of incisors, 10.5; length of nasals, 10; 

 greatest breadth of rostrum, 4; length of upper tooth row, 4; length 

 of mandible, angle to alveolus of incisors, n. 



168. gaurus (Peromyscus), Elliot, Pub. Field Columb. Mus., in, 



1903, p. 157. Zoology. 

 FRISKY MOUSE. 



Type locality. San Antonio, San Pedro Martir Mountains, Lower 

 California, Mexico. 



Genl. Char. Size large, tail very long, colors pale. Skull with 

 broad braincase; nasals long; interorbital space broad. 



Color. Above ochraceous buff, finely lined with black; deepest 

 and brightest on lower back and rump, becoming grayish cream buff; 

 lined with black on upper back and top of head and nose, cheeks, 

 sides, thighs, and upper parts of arms, legs, and entire under parts 

 pure white, the plumbeous under fur showing through; hands and 

 feet white; tail above dark wood brown, beneath cream color; ears 

 blackish brown. 



Measurements. Total length, 222; tail vertebrae, 122; hind foot, 

 22; ear, 20. Skull: occipito-nasal length, 27; Hensel. 21; zygomatic 



