154 Mr. G. DoUman on the 



or "liumpccP^ skull, the iuterorbital region being raised up 

 into a regular hump, from which point the nasals slope 

 markedly downwards anteriorly, and similarly the cranial 

 region j)OSteriorly, the iuterorbital or frontal angle so formed 

 being most conspicuous ; owing to this feature the deptii 

 from the highest point oF the orbit to the alveolar bor(h?r is 

 very great. The general colour is given by Osgood as 

 "from pale cinnamon to wood-brown"; specimens in the 

 Museum Collection identified by the describer seem to agree 

 with this description quite closely. Behind the cars is a 

 conspicuous patch of creamy butf, a feature well developed in 

 the following race. Hands and feet creamy buff. Under- 

 parts slate-grey washed with brown. 



Skull: in addition to the curious arched character men- 

 tioned above, the nasals are rather narrow posteriorly, of the 

 same spoon-shaped pattern as those ot tropicalis. vi^ with 

 7 laminaj. 



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



Head and body 184: mm.; tail 98; hind foot 30-5; 

 ear 24. 



Skull : greatest length 43*3 ; basilar length 34*6 ; zygo- 

 matic breadth 21*7 ; length of nasals 20*7 ; greatest breadth 

 of nasals 7'5 ; iuterorbital constriction 3*4 ; depth from 

 highest point of orbit to alveolar border at front of m^ 14*5 ; 

 postpalatal length 15*1 ; palatal foramina 7'5 ; length of 

 upper molar series 0*2; greatest width of in^ 2"5. 



Bah. Molo, British East Africa. 



Type. Adult female. In Field Museum of Natural 

 Historj', no. 16G98. 



(4) Otomys tliomasi malleus, subsp. n. 



Allied to 0. thomasi, Osg., smaller in size and paler in 

 colour. 



General proportions conspicuously less than in thomasi. 

 Colour of dorsal surface pale ochreous buff suffused with 

 brownish on the back, the general effect paler and greyer 

 than in the Molo form. Flaidcs pale buff. Head and 

 muzzle similar in colour to back, cheeks pale buff. Light 

 areas behind ears much as in thomasi, but not so prominent. 

 Backs of hands and feet light greyish white washed with 

 pale buff. TJnderparts of boily slate-grey overlaid with pale 

 buff". Tail greyish white tinted with buff. 



Skull of the same arched tyne as that of thomasi, but 

 decidedly smaller and with much shorter nasals. 



