new African Mammals. 283 



representatives in the central part of East Africa; most 

 richly coloured part of rump barely " ochraceous buff/' sides 

 of rump " buff." Head as usual greyer. Sides of muzzle 

 without dark whisker marks. An unusually well-marked 

 buffy supraorbital spot. Ears dull buffy, a patch of dull 

 whitish buffy on the crown internal to the ear. Hands 

 white ; front of forearms, whole of lower legs, and upper side 

 of feet clear buffy. 



Skull as in true surdaster. 



Dimensions of I he type (measured in the flesh) : — 



Head and body 115 mm.; tail 165 ; hind foot 23; ear 17. 



Skull: greatest length 29; zygomatic breadth 14 ; inter- 

 orbital breadth 4'5 ; palatal length 13*6; length of upper 

 tooth series 4*5. 



Hah. Mr. Elgon. Type from Malikisi, 5000'. An im- 

 mature specimen from Kirui, 6000'. 



Type. Adult male. Rudd Collection. Original number 

 478. Collected 29th November, 1909, by Robin Kemp. 



This Elgon Bush-mouse is readily distinguishable by its 

 pale colour and buffy supraorbital spots from the form of 

 T. surdaster which occurs in the central region of British 

 East Africa. Like true Nyasa surdaster it lias no dark 

 whisker marks. 



Thamnomys discolor, sp. n. 



A dark-coloured species of the dryas-surdaster section of 

 the genus, with grey head, buffy under side, and parti- 

 coloured feet. 



Size rather small. General tone dark brownish, the brightest 

 part of the hinder back cinnamon. Under surface white, 

 tinged with buffy, the sides of the belly each with a broad 

 and conspicuous pinkish-buff line edging the darker colour 

 of the sides, and extending inwards nearly across the belly. 

 Face dark grey (about grey no. 5) markedly contrasted with 

 the fulvous brown body-colour which extends forward to the 

 crown. No dark whisker marks or light supraorbital spots. 

 Ears dull buffy. Front of forearms grey. Hands bright 

 buff, an indistinct slaty patch on the metacarpus. Hind legs 

 dull fulvous behind, their inner aspect pinkish buff in con- 

 tinuation with the buffy lateral lines ; upper surface of feet buff, 

 with a large patch of brownish grey on the outer half (inner 

 in the prepared skin) of each metatarsus. 



Size of teeth about as in T. surdaster. 



Dimensions of the type (measured in skin) : — 



Head and body 115 mm.; tail 176; hind foot 23*5. 



20* 



