48S Mr. G. Dollman on Two 



b. Size-.of body smaller (lie.ad and body about 

 90 mm. in length). 

 a'. Dor.sal surface pale greyish butf; imder- 



parts pure white. Spines slender pulchellus. 



b'. Dorsal surface slate-grey ; underparts dirty 



grey, never pure white. Spines coarse . . percivali. 

 B, Tail short, never more than 70 miu. in length. 



a. Tail more than 60 mm. in length (avex'age 



length 66). General colour of back dark 

 sepia-brown nuhilus. 



b. Tail less than 60 mm. in length (average length 



50 mm.). 

 a' . General colour bright rufous orange speckled 



with brown , tvilsoni. 



b'. General colour drab-brown speckled with 



pale buft". Size rather smaller iv. ablutus. 



LXIV. — Two new Pigmy Gerhils from British East Africa. 

 By Guy Dollman. 



(Published by permission of the Trustees of the British Museum.) 



Dipodillus percivalif sp. n. 



Intermediate in size between Dipodillus diminutus, Dollm., 

 and JJ. harwoodi, Tlios. 



General colour of dorsal surface rather riclier tliau in 

 diminutus, on the back the effect is almost as rich as in the 

 '' amber-brown '' of Hidgway (1912), gradually becoming- 

 paler on the flanks (between " ochraceous tawny " and 

 " cinnamon "). Backs of hands and feet and ventral surface 

 of body white. Tail like that of harwoodi. 



Skull considerably larger than that of diminutus, but not 

 as large as in the Naivaslia species. 



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



Head and body 78 mm. ; tail 102 ; hind foot 20 ; 

 ear 11. 



Skull : greatest length 23*7 ; basilar length 16-8 ; length 

 of nasals 8'5 ; zygomatic breadth 12*2 ; interorbital con- 

 striction 4; breadth across brain-case 11*5; length of 

 anterior palatal foramina 4'3; length of upper cheek-teeth 

 (from front alveolar border to back of last molar) 3"6. 



Hah. Voi, Briti.sh East Africa. Altitude 2500 feet. 



Type. Adult female. Original number 1544. Collected 

 and" presented to the British Museum by A. Blayney 

 Percival^ Esq. 



