232 



U.S. NATIONAL MUSEUM BULLETIN 2 75 



Jaculus jaculus cufrensis. Cyrenaica: Environs of Cufra Oasis. 



Jaculus jaculus tripolitanicus. Tripolitania: Gefara plain. 



Jaculus jaculus whitchurchi. Cyrenaica: Coastal plain of Gulf of 

 Sirte, and Giarabub Oasis. 



Published records in Libya. Cyrenaica: Giarabub (de Beaux, 

 1928); El Agheila, Cufra (de Beaux, 1932); Giarabub (Zavattari, 

 1937); Zauia Mechili (de Beaux, 1938); Giarabub, Gialo, Marada, 

 Tazerbo (Toschi, 1951); Tripolitania: Socna, "AttickLoumonileh", 

 "Oumsinerma" (Thomas, 1902); Tripoli (Klaptocz, 1909); Sirte 

 (Zavattari, 1937); Tripolitania settentrionale (Toschi, 1951); Fezzan: 

 Murzuch, Serdeles, Bir el Fatima (Toschi, 1951). 



Remarks. The present study reveals that jerboas of this species 

 are an assemblage of rather localized populations showing consider- 

 able differentiation resulting from relatively long periods of isolation 

 of allopatric populations and ensuing genetic fixation. Local differ- 

 entiation of these jerboas is demonstrable in several areas in Libya. 

 These areas may be delineated as the oases and serirs of central and 

 southern Cyrenaica, the oases and intervening wadis of the Fezzan, 

 and the littoral deserts along the Gulf of Sirte in Tripolitania. This 

 latter region is divisible into two distinct areas — the broad coastal 



Jaculus jaculus 

 I arenaceous 



2 collinsi 



3 cufrensis 



4 tripolitanicus 



5 whitchurchi 



Figure 50. — Distribution of the subspecies of Jaculus jaculus. 



