Mammals from Somaliland. 103 



Its upper molars have respectively three, two, and one 

 separate laminae, placed very obliquely, without any evidence 

 of the more cuspidate character of the teeth of JDipodillus, 

 though younger specimens are needed before they can be 

 accurately described. Below the anterior molar is quite 

 peculiar in shape (see figure B), its narrow anterior lobe and 

 the minute secondary cusps present on its outer side and at 

 its postero-internal angle being without any resemblance to 

 what is found in Dipodillus or other members of tiie Ger- 

 billinai. The second lower molar has also a minute secondary 

 antero-external cusp. 



Mus aJbipes, Riipp, 



S. 124. Harar, 



14. Mus sp. (multimammate). 

 ^. 131. Jig-jiga. 



15. Acomys sp. 



? . 150. Hargeisa. 

 A pale rufous form perhaps referable to A. Hunteri^ de Wint. 



16. Acomys mullah, sp. n. 



(J. 123; ?. 125. Harar. 



Size fairly large. Spinous system less developed than 

 usual, the covering of the head, nape, and fore back rather 

 hispid than spinous, markedly less harsh than in the allied 

 species; spines of back about 11 mm. in length. General 

 colour of headj nape, and fore back pale slaty greyish, the 

 spines of the hinder back becoming tipped with fawn-colour 

 or vinaceous buffy ; posterior flanks and outer side of hips 

 more uniformly of the latter colour. Under surface and 

 inner side of limbs wholly sharply-defined pure white ; outer 

 side of forearms to wrists and legs to ankles grey with a 

 tinge of fawn ; hands and feet white. Ears of medium size, 

 much smaller than in A. dimidiatus. Tail thinly haired, 

 grey above, white below. 



Skull with a very large broad and flat brain-case, the 

 ridges not unusually heavy. Palatal foramina very long, 

 reaching nearly to the level of the posterior fourth of m}. 



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



Head and body 111 mm. ; tail 109; hind foot 18; ear 18. 



Skull: greatest length 31*5; basilar length 24*6 ; zygo- 

 matic breadth 15 ; nasals 13 ; interorbital breadth 5*1 ; 



