and allied East-African Species. 317 



Dimensions in millimetres (measured in the flosli) : — 



Average of 

 3 ftdults. 



Head and body loo 



Tail 107 



Iliud foot 27-5 



Ailiilt skull : greatest length 34"3 mm. ; basilar length 29 ; 

 coiiilylo-incisive length 33; zygomatic breadtli 18; inter- 

 orbital constriction 5 ; squamosal breadth o£ cranium 13*G ; 

 length of nasals 13'2 ; palatilar length 15"G; length of 

 palatal tbramijia 7 ; alveolar length of upper molar series 7. 



Type locaJity. Nairobi, British East Africa. 



In the British Museum are three specimens from the type 

 locality, and from these the above description has been taken. 



I (11) Arvicantliis abyssinicus prcBceps, Wrought. 



Arvtcanthis n. praceps, Wrougliton, Ann. & Mag. Nat. Hist. (8) iv. 

 p. 538 (1909). 



Closely allied to the foregoing form, differing only in the 

 hands and feet being golden yellow and the under surface 

 strongly tinted with buff. 



Size of body about as in nairohcv, tail rather longer 

 (111 mm.), hind foot a little smaller. General colour of 

 dortal surface quite sinnlar to that of nairohce. No dorsal 

 stripe. Backs of hands and feet richly tinted with orange- 

 buff". Ventral surface of body dirty greyish white, washed 

 ■with buff. Tail like that of nairobce, but rather lighter 

 above. 



Skull very much like that of nairolxe^ molars rather smaller, 

 but not markedly so. Brain-case narrow. 



The skull measured below is that of an old Baringo 

 specimen. 



Dimensions in millimetres (measured in the flesh) : — 



Average of 



10 adults. Max. Miu. 



Head and body 142 152 131 



Tail Ill 116 108 



Hind foot 266 28 25 



Adult skull : greatest length 3-l"5 mm. ; basilar length 28'3 ; 

 condylo-incisive length 33 ; zygomatic breadth 17*5; inter- 

 orbital constriction 5 ; squamosal breadth of cranium 13*5; 

 length of nasals 13 ; palatilar length 15"3 ; length of palatal 

 foramina 7 ; alveolar length of upper molar series 6*5. 



