MAMMALS OF ANGLO-EGYPTIAN SUDiU^ — SETZER 537 



Specimens Examined: Sixteen, all in BM, from: El Fasher, 15; 

 40 miles west of El Fasher, 1. 



Diagnosis: Upperparts near Mars Yellow, underparts, cheeks, 

 hands, feet, suborbital and supra-amicular spots pm-e white. Skull 

 relatively massive, rostrum long and narrow, braincase moderately 

 well inflated, anterior palatine foramina relatively long, bullae mod- 

 erately well inflated. 



Measurements of the Type Specimen: Length of head and body 

 94; length of tail 93; length of hind foot 17; length of ear 15; greatest 

 length of skidl 28.9; condyloincisive length 26.0; length of anterior 

 palatine foramina 6.6; crown length of upper toothrow 4.6; least inter- 

 orbital width 4.9; width of rostrum at level of antorbital foramen 3.1 ; 

 length of nasals 11.2; greatest width across zj'gomatic arches 13.6. 



Comparisons: From Acomys cahirinus cineraceus as kno\vn by 

 specimens from El Kowa, A. lowei differs in markedly lighter color, 

 less arched skull, larger bullae, longer anterior palatine foramina, 

 longer rostrum, and longer nasals. 



From Acomys cahirinus cahirinus from Giza, Egypt, A. lowei 

 differs in markedly lighter color. The skull is more inflated in the 

 region of the braincase, the nasals are somewhat longer, the auditory 

 bullae are less inflated, there is a somewhat different shape in the 

 pterygoid region, the upper incisors are narrower, and the anterior 

 palatine foramina are somewhat shorter and more bowed laterally. 



From Acomys intermedius from 20 miles west of Nahud, A. lowei 

 differs in lighter, brighter color and lighter colored tail. The skuU is 

 larger and more robust in all respects. 



From Acomys cahirinus hunteri from Erkowit, A. lowei differs in 

 lighter color, somewhat smaller skull, and markedly smaller auditory 

 bullae. 



Remarks: These specimens were originally identified as Acomys 

 witherbyi by Thomas in the Darfur report of 1923. Since that time 

 the name witherbyi has been shown to be a synonym of A. cineraceus, 

 which is now considered to be only a subspecies of A. cahirinus. 

 Since the animals from the vicinity of El Fasher vary from the animals 

 from El Kowa and its environs as set forth under the section on 

 comparisons, it is obvious that they are not closely allied. When 

 the genus Acomys is studied in detail probably many more of the 

 species will fall as synonyms or be relegated to subspecific status, 

 but until the genus is studied I do not see the advantage of arbitrarily 

 relegating all species to subspecific status of the earliest named 

 species in the genus such as has been done in the recent book of 

 EUerman, Morrison-Scott, and Hayman (1953) on the mammals of 

 Southern Africa. 



