EAST AFRICAN MAMMALS, 311 
26. GRAPHIURUS BROCKMANI INTERNUS Dollm. 
©. 100. Narossura River. 
@. 105, 109. Southern Guaso Nyiro, 
These Dormice do not appear to differ from the specimens 
collected by Mr. Blayney Percival and Mr. Robin Kemp on the 
Northern Guaso Nyiro, the type locality of this race. 
27. DipopiLLus HARWoopI Thos. 
3. 118. Southern Guaso Nyiro. 
This diminutive Gerbil is evidently widely distributed over 
the southern portion of British Hast Africa. The type locality 
of the species is Naivasha, but it would appear to extend much 
further south than many Naivasha mammals; Dr. Bayer obtained 
a Dipodillus harwoodi from as far south as the Tsavo River. 
This specimen, which is in the collection of the Congo Museum, 
Tervueren, | have recently had an opportunity of examining, 
and there would appear to be no doubt that it represents the 
Naivasha species. 
28. GERBILLUS COSENST Dollm. 
Abstract P. Z.S. 1914, p. 25. (April 14.) 
$. 170. Kozibiri River, Ngamatak, Turkwel River. Alti- 
tude 1800 feet. 
Allied to Gerbillus dunni Thos., the Somali species, but readily 
distinguished by its duller colour and smaller size. 
General proportions rather less than in dunni, the hind foot 
measuring only 25 mm. in length. 
General colour of dorsal surface pale buff mixed with slate- 
erey, the grey tint most obvious on the shoulders and down the 
middle of the back; flanks brownish buff, near ‘‘ warm buff” 
(Ridgway, 1912). Head similar in colour to back, the slate-grey 
bases of the hairs showing through the yellowish-buff tips, 
Sides of face white; pale greyish-buff markings extending from 
below the eyes to the ears. Backs of hands and feet white. 
Entire ventral surface pure white. Dorsal surface of tail much 
darker than in dunni, above dirty brown, below white. 
The skull of this unique specimen is unfortunately badly 
broken, all the region posterior to the frontals and palate being 
missing. Compared with the skull of the Somali species the 
general structure would appear to be very much the same, but 
rather smaller throughout. 
Dimensions of the type (measured in the flesh) :— 
Head and body 78 mm.; tail 129; hind foot 25; ear 14. 
Skull (posterior part of skull broken): length from fronto- 
parietal suture to tip of nasals 19°5 mm.; length of nasals 10; 
greatest breadth across nasals 2-4; interorbital constriction 5; 
length of anterior palatal foramen 4; length of posterior palatal 
cavities 2°2 ; alveolar length of upper molar series 4. 
