MAMMALS OF ANGLO-EGYPTIAN SUDAN — SETZER 521 



Mastomys natalensis blainei (Wroughton) 



Figure 7,a 



Mus blainei Wroughton, Ann. Mag. Nat. Hist., ser. 7, vol. 20, p. 502, December 

 1907. (Chak Chak, Bahr-el-Ghazal.) 



Specimens Examined: Twenty-three, all in BM, from: Moyen, 1; 

 Wau, 8; Tembura, 5; Katta, 1; Chak Chak, 8. 



Measurements: An adult male from Chak Chak measures as fol- 

 lows: Length of head and body 125; length of tail 115; length of hind 

 foot 25; length of ear 17; length of anterior palatine foramina 7.5; 

 crown length of upper toothrow 4.6; least interorbital width 4.5; width 

 of rostrum at level of antorbital foramen 3.8; length of nasals 12.1; 

 greatest width across zygomatic arches 15.3. 



Remarks: M. n. blainei is generally darker in color than any of the 

 surrounding kinds with the exception of M. n. macrolepis. It may be 

 distinguished from the latter by its much narrower zygomatic arches 

 and narrower rostrum. From the other subspecies adjacent to blainei 

 it may be distinguished cranially by its narrower rostrum and generally 

 wider zygomatic arches. 



Mastomys natalensis ismailiae (Heller) 



Figure 7,a 



Epimys concha (sic) ismailiae Heller, Smithsonian Misc. Coll., vol. 63, No. 7, p. 9, 

 June 24, 1914. (Gondokoro.) 



Specimens Examined: One hundred and thirteen, from: Obbo, 23; 

 Torit, 27 (4, MCZ); Juba, 6 (2, BM); Nimule, 10 (1, MCZ); Lotti 

 Forest, 1 ; Magwe, 36 miles southwest of Torit, 2 (MCZ) ; Mongalla, 

 10 (BM); Malek, 7 (BM);Bor, 5 (BM); Duk, 2 (BM); Evos, Didmga 

 Mountains, 1 (BM); Towat Boma, 2 (BM); Kagula, 6 (BM); Lake 

 No, 2 (BM); Gondokoro, 1 (BM); no locality, 1; Kaka, 3 (BM); 

 Fashoda, 4 (BM). 



Measurements: An adult male and an adult female from Juba 

 measure, respectively, as follows: Length of head and body 143, 143 

 length of tail 127, 128; length of hind foot 28, 27; length of ear 16, 16 

 greatest length of skull 32.9, ?; condyloincisive length 31.1, 31.5 

 greatest width across zygomatic arches 15.7, 16.2; least interorbital 

 width 5.0, 4.6; length of nasals 13.8, 13.2; crown length of upper tooth- 

 row 4.9, 5.2; length of anterior palatine foramina 8.1, 7.8. 



Remarks: In spite of the large number of specimens of this sub- 

 species available for study, only a few were fully adult. Of those that 

 were adult, few had complete crania which could be measured. 



