88 BULLETIN 99, UNITED STATES NATIONAL MUSEUM. 



names represent large and small individuals of the same subspecies, 

 perhaps to be recognized as a valid race of coucha inhabiting the 

 Baringo region. 



The Gondokoro race of coucha, described by Heller as Epimys 

 coucha ismailise, is not a very well-marked form and differs from 

 Rattus coucha ugandse only in its brighter, more cinnamon rufous 

 coloration, and smaller size, both of which are average characters, 

 not entirely constant throughout the series. The color of the under- 

 parts is uniformly creamy whitish, more or less mixed with the gray 

 of the underfur; no individuals with drab-colored bellies, not uncom- 

 mon in other races, are in the collection. The largest specimens, and 

 also the oldest as shown by the condition of the skulls and teeth, are 

 decidedly grayish in color, with very little of the cinnamon tones 

 characteristic of the average younger adult specimens of the race. 

 Our specimens of this subspecies are all from the east side of the 

 Nile in extreme northwestern Uganda, between Gondokoro and 

 Nimule. 



For detailed measurements of specimens of this subspecies, and of 

 other forms of the subgenus Mastomys, see tables, pages 90-93. 



RATTUS COUCHA UGANDSE (de Wiiiton). 



1897. Mus ugandag de Winton, Ann. and Mag. Nat. Hist., ser. 6, vol. 20, p? 317. 



September. (Entebbe, Uganda; type in British Museum.) 

 1910. Epimys ugandse Roosevelt, African Game Trails, Amer. ed., p. 473; 



London ed., p. 485. 

 1918. Rattus coucha ugandse Hollister, Smithsonian Misc. Coll. vol. 68, No. 10, 



p. 1. January 16. 



Specimens. — Fifty-three, from the following localities: 



Lado: Rhino Camp, 11, including 3 odd skulls (Loring). 



Uganda: Hoima, 2, including 1 in alcohol and 1 odd skull (Lor- 

 ing); Kabula Muliro, 9, including 2 in alcohol and 1 odd skuU (Lor- 

 ing); Kampala, 5, including 3 in alcohol (Mearns, Heller, Loring); 

 Kikanda, 5 (Loring); Kikandwa, 2 (Loring); Kisimbiri, 2 (Loring); 

 Kisingo, 9 (Loring); Lialo, 8 (Loring). 



The distribution of this race is doubtless continuous between the 

 Lado and the northern shores of Victoria Nyanza by way of eastern 

 Belgian Congo and the Ruwenzori country. How far it extends 

 northward on the eastern side of the White Nile before blending into 

 the Gondokoro form, Rattus coucha ismailise, is not known, as no 

 specimens are available from this district between the Victoria Nile 

 and Nimule. The large, brown-bellied skins of ugandx in the col- 

 lection are usually those specimens with the largest, most angular 

 skulls in which the teeth are very much worn. The majority of the 

 specimens have grayish-white underparts. 



