550 



MERRIAM 



REITHRODONTOMYS PEROTENSIS sp. nov. 



Type from Cofra de Perote, Vera Cruz, Mexico (altitude 9,500 ft.). 



No. 54424. $ ad. U. S. National Museum, Biological Survey 



Coll. May 31, 1893. E. W. Nelson and E. A. Goldman. Orig. 



no. 4912. 



Characters. — Pelage long, soft, and woolly; ears large and dark; 

 tail medium; similar in general to cZ/rj^o/^w but color everywhere 

 duller; top of head and middle part of back darker; skull and teeth 



much smaller. 



Color. — Upperparts pale dull yellowish fulvous, tending toward 

 buffy gray on head and toward fulvous on rump ; top of head and 

 back profusely lined with black hairs, most abundant along median line 

 where they form a dark median dorsal area extending to base of tail ; 

 underparts buffy salmon, ankles and wrists brownish ; fore and hind 

 feet whitish ; tail dark above, indistinctly paler below. 



Cranial characters. — Skull in general similar to that of chrysopsls 

 but smaller; braincase flatter; zygomata squarely spreading anteriorly, 

 their outer sides parallel ; rostrum shorter but equally slender ; nasals 

 ending on plane of premaxilhe ; incisive foramina long and open; 

 length of upper molar series 3.30 (contrasted with 3. So in chrysopsis). 



Measurements. — Type specimen {$ ad.): total length 176 mm.; 

 tail vertebras 102; hind foot 19. 



REITHRODONTOMYS ORIZAB^^ sp. nov. 



Type from Mount Orizaba, Puebla, Mexico (altitude 9,500 ft.). 



No. 53626. $ ad. U. S. National Museum, Biological Survey Coll. 



April 24, 1S93. E. W. Nelson and E. A. Goldman. Orig. 



no. 4734. 



Characters. — Size medium; ears blackish and well haired; tail 

 long and rather slender; pelage long, soft and woolly; closely related 

 to chrysopsis and perotensis. 



Color. — Upperparts golden fulvous, becoming fulvous on rump, 

 slightly darkened on posterior part of back with dark tipped hairs (al- 

 most exactly as in chrysopsis) \ lips and chin grayish; underparts 

 buffy salmon; tail dark above, indistinctly paler below; wrists and 

 ankles dark ; fore and hind feet whitish. 



Cranial characters. — Skull similar to that oi perotensis but rostrum 

 slightly broader; braincase narrower and more rounded; bullie more 

 transverse ; molar teeth as in perotensis. 



Rctnarks. — Externally orizabcc is hardly distinguishable from the 

 more highly colored specimens of chrysopsis, although the head is 

 more strongly fulvous, the ears decidedly more hairy, and the tail less 



