new Sout/i- American Mammalg. 1!>1 



white. Arms and \e^s like back ; wrists an<l ankles rufous ; 

 liands and fi-et blackish. Under surfact' dark brown, th»i 

 chest and inidillc line of billy j)roniinfntlv' ^nizzled with 

 whitish. Tail, as usual, broadly washc-d with white. 



Dimensions of the typ(> (measured in skin) : — 



Head arid body 270 millim. ; tail MO ; hind foot (wet) 57; 

 ear (wet) 2(3. 



IJah. of type, Balzar Mountains, on tho Upper Palenque 

 River, W. Ecuador. Another specimen from Chon^^on 

 (Simons). 



Tupe (male). B.M. no. 80. 5. 6. 81. Collected by 

 Mr. lllinj:^worth. 



The three races now recognized may be briefly distin- 

 guished as follows : — 



S. stramineus it/picus. — General colour dark ; no nuchal 

 patch. Under surface dark brown. 



S. s. Sibou.rii. — General colour light; a nuchal patch. 

 Under surface pale ^rey. 



S. s. giiayinus. — General colour pale; no nuchal patch. 

 Under surface brown, grey mesially. 



Fhyllotis gerbilluSy sp. n. 



A small species, not unlike a Peromyscus in general pro- 

 portions, with typical desert-coloration, such as is found in 

 many Gerbilles ; quite uidike any Neotropical species hitherto 

 described. 



kSize rather larger than in Mns mnsculus. Fur soft, sleek 

 and shiny, the hairs about 5-6 millim. long on the back. 

 General colour of head and back clear sandy fawn, rather 

 variable in tone, but on the whole very similar to that of the 

 Egyptian Gcrhillus gerhillus. Individually the hairs are 

 slaty at their bases, then whitish, with their visible ends 

 fawn, finely tipped with blackish. Ears proportionally large, 

 pale grey. Under surface wholly pure white, the line of 

 demarcation fairly well marked, and so iiigh that the white 

 includes the wIkjIc of the limbs, fore and hind, from the 

 shoulders and hips downwards, the fawn not extending on 

 to the limbs at all. Tail fairly well haired, faintly pencilled, 

 wholly white, or the median line above slightly darker. 



Skull practically a miniature of that of Ph. Haggardi^ but 

 the zygomata rather more widely expanded. 



Dimensions of the type (measured in the flesh by col- 

 lector) : — 



Head and body 82 mdlim.; tail 90; hind foot (s. u.) 20; 

 ear 17. 



tskull : greatest length 24; basilar length 18; zygomatic 



