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U.S. NATIONAL MUSEUM BULLETIN 275 



Figure 25. — Distribution of Gerbillus amoenus vivax. Circles indicate specimens examined; 

 triangle indicates published record. 



Measurements. Averages and extremes of 10 adult males and the 

 measurements of 3 adult females from Goddua, Fezzan Province, are 

 respectively: Total length 202.2 (187-213), 203, 200, 202; length of 

 tail 112.9 (97-124), 113, 110, 115; length of hind foot 23.2 (22-23), 

 23, 23, 23; length of ear 12.4 (12-13), 12, 12, 13; occipitonasal length 

 of skull 25.6 (25.2-26.3), 26.8, 25.3, 26.4; length of auditory bulla 9.7 

 (9.5-10.1), 9.7, 9.6, 9.8; length of upper molariform toothrow 3.3 

 (3.2-3.4), 3.3, 3.4, 3.4; greatest breadth across zygomatic arches 13.7 

 (13.4-14.5), 14.5, 13.6, 13.8; least interorbital breadth 4.6 (4.4-4.8), 

 4.7, 4.3, 4.5; breadth of rostrum at level of antorbital foramina 2.7 

 (2.5-2.9), 2.9, 2.7, 2.7; length of nasals 9.4 (9.3-9.7), 10.4, 9.4, 10.1. 



Diagnosis. Upperparts grading from Cinnamon-Buff to Clay Color, 

 becoming paler on sides owing to suffusion of white; entire dorsum 

 with uniform admixture of brown; plumbeous underfur exposed on 

 dorsum in most specimens; postauricular patches conspicuous and 

 white; pelage around ears and eyes subdued in color, approaching 

 Light Buff, and strongly suffused with gray; a distinct grayish patch 

 (typical of all members of this species) between the base of the pinna 



