550 MESSRS. THOMAS AND WKOUGHTON ON [May 26, 



Ty2-)e. Old female. B.M. no. 6.11.8.115. Original number 

 1644. Collected by Mr. C. H. B. Grant, 18th August, 1906 (Rudd 

 Exploration). 



Three specimens examined. The proportionally very long tail, 

 the smaller teeth and bullse, and the extension forward of the 

 palatal foramina almost to the henselion serve to distinguish 

 cometes at once from ruddi, which in colour it so closely 

 resembles. 



Thamnomys surdaster, sp. n. 



A smaller Thamnomys belonging to the same group as the two 

 described above, but with smaller skull, teeth, and bullfe, and 

 colovir-pattern as in the riitilans-gron^. 



Size somewhat smaller than in T. rttddi. Fur soft, short 

 (7-8 mm. on the back). General ground-colour above "clay- 

 colour," with strong tawny suffusion on rump and lower back, 

 often extending forward even to the crown ; below pure white. 

 Hands and feet buff, fingers and toes white. 



Skull small, teeth and bullse very small. 



Dimensions : — 



Head and body (c.) 110 mm. ; tail 160 ; hind foot 22 ; ear 18. 



Skull — greatest length 29 ; basilar length 22 ; greatest 

 breadth 14; brain-case breadth 12; interorbital breadth 4*5; 

 nasals length 10"6 ; palatal foramina 5*8 ; diastema 7"2 ; upper 

 molar series 4 ; bullse 5. 



JIab. Nyasaland and North-East Rhodesia. (Type from 

 Zomba.) 



Type. Adult. B.M. no. 93.5.2.27. Collected by Mr. A. Whyte 

 in October 1892 and presented by Sir H. H. Johnston. 



Three specimens from Zomba examined. The Museum has an 

 example from Angoniland and one from the East Loangwa 

 District (collected by Mr. S. A. Neave), which also appear to 

 belong to this species. 



26. Saccostomus campestris Peters. 



J. 1948, 1977. 



Topotypes of species*. 



These specimens confirm our opinion that in South Africa 

 there are two forms in this genus, the smaller ones represented 

 by S. campestris, and a larger, for which the oldest name is 

 S. mashonce de Wint. 



" Native name, ' Psuku.' 



"^ Apparently rather scarce and usually taken in native culti- 

 vation along the banks of the rivers. 



" The cheek-pouches of the specimens sent contained sweet 

 potato."— C. H. B. G. 



* Reis. Mossamb. 1852, p. 167, pL xxxiv. fig. 3 & pi. xxxv. fig. 12. 



