MAMMALS OF ANGLO-EGYPTIAN SUDAN — SETZER 523 



Specimens Examined: Nineteen, all in BM, from: Kulme, Wadi 

 Aribo, 14; Niurmya, 1; Kurra, Jebel Marra, 3; Jebel Marra, 1. 



Diagnosis: Upperparts, in general tone, near Saccardo's Umber. 

 The pure color band of the hairs are near Sayal Brown but because of 

 the intense admixture of black the darker color is apparent. Under- 

 parts plumbeous, but lightly tipped with bufty white. Hands and 

 feet white, tail dark, nearly naked, and of uniform color above and 

 below. Skull relatively large and robust; anterior palatine foramina 

 long; upper too throw relatively heavy; auditory bullae moderately 

 well developed; rostrum, in general, heavy; zygomatic arches nearly 

 parallel-sided, not tending to bow laterad excessively. 



Measurements of the Type Specimen: Length of head and 

 body 145; length of tail 127; length of hind foot 28; length of ear 18; 

 greatest length of skull 32.7; condyloincisive length 30.9; length of 

 anterior palatine foramina 7.6; crown length of upper toothrow 4.8; 

 least interorbital width 4.2; width of rostrum 4.1; length of nasals 

 14.1; greatest width across zygomatic arches 16.0. 



Comparisons: M. n. marrensis differs from M. n. ugandae in 

 slightly paler color both above and below, the buffy wash of the belly 

 being somewhat more pronounced. The skull is somewhat longer 

 and more slender; the zygomata not flaring so much; auditory bullae 

 smaller; rostrum longer and narrower; pterygoid region shorter 

 anteroposteriorly. 



From M. n. blainei, M. n. marrensis differs in darker color, longer 

 hind foot, and longer tail. The skull is larger in all respects, with the 

 exception that the zygomatic arches are narrower. 



From AI. n. macrolepis, M. n. marrensis is of about the same color 

 but somewhat lighter and smaller in size. The skull is smaller in all 

 respects. The bullae are relatively as well as actuallj^ more inflated, 

 the rostrum is narrower, the pterygoid region is shorter, and the 

 zygomata are less flaring. 



From M. kvlmei, M. n. marrensis is darker, larger in all respects, and 

 shows the same variation in cranial characters as do the other 

 members of the species natalensis. 



Remarks: Two species of Mastomys occur together at Kulme, Wadi 

 Aribo, One, M. n. marrensis is dark and large and is decidedly of the 

 natalensis group, the other, M. kulraei, is relatively small and in no 

 way resembles any member of the natalensis complex. 



Thomas and Hinton (1923, p. 266) referred kulmei to the "wild 

 living" kind macrolepis, and marrensis to the "house living" kind 

 ugandae. It has since been shown that commensalism does not seem 

 to affect the color of these animals and that animals of the same color 



