150 



U.S. NATIONAL MUSEUM BULLETIN 275 



Distribution in Libya. Coastal plain and littoral deserts of 

 Cyrenaica and the uplands of the Gebel Nefusa and Gebel Tigrinna 

 in Tripolitania. 



Specimens examined. Twenty, from Cyrenaica: 3 km E Derna, 

 2; 2 km N Coefia, 6; 8 km N Benghazi, 2; 20 km E Tobruch, 5; 

 from Tripolitania: 20 km E Rumia, 1 ; 12 km S Chicla, 4. 



Measurements. Measurements of one adult male, 325028, and 

 two adult females, 325027 and 325550, from 20 kilometers east of 

 Tobruch, Cyrenaica Province, are, respectively: Total length 164, 

 169, 159; length of tail 83, 81, 77; length of hind foot 21, 21, 20; 

 length of ear 12, 12, 12; occipitonasal length of skull 25.8, 26.3, 24.4; 

 length of auditory bulla 8.4, 8.6, 8.1 ; crown length of upper molariform 

 toothrow 3.5, 3.8, 3.5; greatest breadth across zygomatic arches 

 14.2, 14.2, 13.5; least interorbital breadth 5.1, 4.7, 4.6; breadth of 

 rostrum at level of antorbital foramina 2.7, 2.6, 2.6; length of nasals 

 9.6, 9.7, 9.4. 



Diagnosis. Color of the dorsum varying widely according to 

 geographic locality and ranging from Light Ochraceous-Buff, Cin- 

 namon-Buff, or Tawny Olive to Sayal Brown; complete dorsum 



Gerbillus kaiseri 



Figure 30. — Distribution of Gerbillus kaiseri. 



