RODENTS OF LIBYA 161 



in the single species, M. libycus. He considered M. shawi as a synonym 

 of M. I. libycus and relegated M. crassus to subspecific status. Meriones 

 erythrourus, whose range included Russia and Southwest Asia, was 

 given specific rank but thought possibly to represent only a subspecies 

 of M. libycus. 



In a later paper, Ellerman (1947) further divided the genus into 

 two additional subgenera, Sekeetamys Ellerman and Pallasiomys 

 Heptner, based upon both the hairiness of the hind feet and the 

 relative size of the auditory bullae, and placed all the forms with 

 large bullae, including all of the Libyan forms, in the subgenus 

 Pallasiomys. In addition, M. crassus was elevated to specific rank and 

 M. shawi withdrawn from synonymy and established as a subspecies 

 of M. libycus. Thus the Libyan representatives of this genus were 

 treated as two full species, M. libycus and M. crassus. 



Later in the year Ellerman and Chaworth-Musters in "A Revision 

 of the Genus Meriones" (1947), because of the sympatry of M. I. 

 shawi and M. I. caudatus, separated M. shawi specifically from both 

 M. crassus aud M. libycus. The above authors separated M. libycus 

 from the other two species by certain external characters (hind claws 

 d&rk= libycus; hind claws p&\e=crassus and shawi), and M. crassus 

 and M. shawi were distinguished by the size of the auditory bullae 

 (large in crassus; small in shawi). In addition to the coloration of the 

 hind claws, the degree of closure of the suprameatal processes was 

 given as a character separating M. crassus and M. libycus. 



Toschi (1954) also recognized three species of the genus Meriones 

 in the Libyan fauna, M. libycus, M. crassus, and M. shawi, represented 

 by five subspecies, including the nominate subspecies of all three 

 species and M. libycus caudatus and M. I. conjalonierii de Beaux. Setzer 

 (1957), the most recent worker on Libyan mammals, included the 

 same three species in the Libyan fauna but considered M. crassus 

 tripolius distinct from M. c. crassus and did not recognize M. libycus 

 libycus and M. c. crassus as occurring in Libya. In addition, he de- 

 scribed M. shawi azizi as a new subspecies from the northern Cyrenai- 

 can coast. Later, in reviewing the mammals of Egypt, Setzer (1961) 

 did not consider M. shawi as part of the Egyptian fauna and, further- 

 more, questioned its validity as a species. He was unable to find any 

 specific differences between M. shawi and M. libycus and concluded 

 that the former was probably conspecific with M. libycus farther west 

 in North Africa. The present author also doubts the validity of the 

 species M. shawi. 



Specimens from coastal Libya, formerly referred to Meriones shawi 

 shawi and Meriones shawi azizi by Setzer (1957), are now considered 

 to be referable to Meriones libycus and are now known, respectively, as 

 Meriones libycus awratus (new subspecies) and Meriones libycus azizi. 



