1908.] MAMMALS FROM ZAMBESIA. 549 



25. Thamnomys ruddi, sp. n. 



c?. 1970. 2- 2033, 2036. 



A Thamnomys, belonging to the group in which the cha.rac- 

 teristic third inner cusps of the vipper molars are reduced to a 

 ridge, and with the mammary formula 1 — ^2 = 6. 



Size about as in 3Iics namaquensis auricomis. Fur soft and 

 fairly long (12 mm. on the back). General colour above near 

 " clay-colour " ; below pure white. Individual hairs of the back 

 basally slate-colour for two-thirds their length, then bufi"; a small 

 proportion of black hairs scattered through the coat ; belly-hairs 

 white to their bases. Hands and feet white. 



Skull with a marked interval (2 mm. or more) between the 

 henselion and the commencement of the palatal foramina. 



Dimensions of the type : — 



Head and body 124 mm. ; tail 160 ; hind foot 22 ; ear 20. 



Skull — greatest length 32'5 ; basilar length 26 ; greatest 

 breadth 15"5 ; brain-case breadth 13"2 ; interorbital breadth 5; 

 nasals leng-th 12 ; palatal foramina 7 ; diastema 8"5 ; upper molar 

 series 5 ; bullae 7. 



Hah. Tette, Portuguese East Africa. 



Type. Old female. B.M. no. 8.4.3.81. Original number 2033. 

 Collected 14th Sept., 1907. Three specimens examined. 



" Native name, ' ISTsunto.' 



" This species, although undoubtedly common, is difficult to 

 secure ov/ing to its arboreal habits. 



" It inhabits the hollows of decayed and dead trees, in which it 

 makes warm nests of leaves, &c., of no particular shape, merely 

 filling up the cavities with debris. 



" Strictly nocturnal ; one specimen was shot at night whilst 

 climbing among the branches of a small tree when I was sitting 

 up for Galago." — C. H. B. G. 



In working out this Thamnomys we have found that the two 

 following forms also require description : — 



Thamnomys cometes, sp. n. 



A Thamnom.ys belonging to the same group and about the 

 same size as the last, but with a markedly longer tail. 



Size as in T. mddi, but tail one-third longer. Fur soft, shorter 

 than in T. ruddi (9-10 mm. on the back). Colour almost exactly 

 as in T. ruddi. Hands and feet white. 



Skull with bullse and teeth smaller, and palatal foramina pro- 

 duced more forward than in T. ruddi. 



Dimensions of the type : — 



Head and body 124 mm. ; tail 195 ; hind foot 24 ; ear 20. 



Skull—greatest length 33-2 ; basilar length 26 ; greatest 

 breadth 15-8; brain-case breadth 13-6; interorbital breadth 5; 

 nasals length 12-5; palatal foramina 8; diastema 8-5; upper 

 molar series 4-5 ; bullse 6. 



Rah. Inhambane, Portuguese East Africa. 



