102 



Mr. O. Thomas on 



donor of tlie present most acceptable addition to our National 

 Collection, differs from any of its group that I have seen by 

 its darker and less bright sandy general colour. No true 

 Gerhillus as now restricted has been described from Somali- 

 land, the nearest being E-hoads's O. pulvinatus from Lake 

 Eudolf, which may be distinguished from it by having the 

 whole of the underside of its tail white. The general resem- 

 blance of G. Dunni to certain species of DipodiUus is very 

 noticeable. 



12. Ammodillus (g. n.) imheUi's, de Wint. 

 Gerhillus imheUis, de Wint. Anc. & Mag. Nat. Hist. (7) i. p. 249 (1898). 



c? . 137. Gerlogobi Wells. 



" In sandy soil close to wells.''^ 



Measurements in the flesh : — Head and body 106 mm. ; 

 tail 144 ; hind foot 27 ; ear 15. 



Eather richer and deeper rufous than the type, which was 

 collected by Mr. C. V. A. Peel at Gondar. The tail of that 

 specimen having been imperfect, Mr. de Winton could only 

 say of it " tail darker above than below, rather sparingly 

 haired '■"; but I am now able to record that while it is very 

 sparingly haired proximally, it changes terminally, and has 

 a well-marked brown brush, the hairs of which may attain 

 8-10 mm. at the tip. 



But, in addition, a further study of this gerbille convinces 

 me that it cannot properly be included in any of the genera 

 now recognized among the group, the characters of the skull, 

 as detailed by the describer, especially the unique absence of 

 the coronoid processes to the mandible, and the details of the 

 dentition preventing its inclusion in DipodiUus, to which 

 alone its naked soles ally it. 



I I 



Eight upper (A) and riglit lower (B) molars of Ammodillus imbellis. 



