NEW RODENTS FROM BRITISH EAST AFRICA 



Bv N. HOLLISTER 



The following' hitherto nndescribed subspecies of rodents haA^e 

 been found in the collections made by the Smithsonian African 

 Expedition in 1909, and by the Rainey African Expedition of 191 1 

 and 1912. 



RATTUS COUCHA TINCTUS, subsp. nov. 



T\pe from Kaimosi, Kavirondo, British East Africa; adult male 

 (teeth moderately worn), skin and skull, U. S. Nat. Museum No. 

 183294. Collected January 24, 191 2, by Edmund Heller. Orig. 

 No. 5188. 



Diagnosis. — A large, dark-colored subspecies of Rattiis concha 

 with the underparts dark grayish buff, drab, or tawny olive (appar- 

 ently never grayisli white as in the related forms). 



Color of type specimen. — Entire upperparts blackish brown, 

 slightly sprinkled with dark clay color. The hairs are broadly dark 

 slate at bases, many of them blackish to tips, while others have a 

 terminal or subterminal ring of clay color or dark tawny. Sides 

 paler than back, with more tawny and less black. Underparts only 

 slightly lighter than sides, the hairs slate at bases and tipped with clay 

 color, with considerable dark from the undercolor showing through. 

 Arms and legs dark brownish to wrist and heel, the hands and feet 

 creamy whitish. Tail blackish brown, slightly lighter at base below. 



This is an average specimen in color, but some skins in the series 

 are somewhat brighter, with more tawny above or below^ All agree 

 in having intensely colored underparts only slightly dift'erentiated 

 from the color of the flanks. 



Skull and teeth essentially as in Rattits concha ugand(C. but averag- 

 ing more robust. 



Measurements. — The type, with dimensions of an older male 

 (No. 183295) in parentheses: Head and body, 160 (160) mm.; 

 tail vertebra, 133 ( 148) ; hind foot from dry skin, 26 (30) ; greatest 

 length of skull. 34.6 (36.1) ; condylobasal length, t,t,.^ (35-o) ; zygo- 

 matic breadth, 16.8 (17.9); mastoid breadth, 13.6 (14.3); upper 

 tooth row, alveoli, 5.5 (5.8). 



Smithsonian Miscellaneous Collections, Vol. 68, No. 10. 



