MAMMALS OF ANGLO-EGYPTIAN SUDAN — SETZER 531 



Remarks: In the only specimen available there are certain differ- 

 ences from the type of M. t. acholi. These differences are in the size 

 of the bullae, the size of M^, length of the anterior palatine foramina, 

 and, externally, in a somewhat darker color. Whether these observ- 

 able differences are geographic, individual, or seasonal cannot be 

 determined at this time. Therefore, this specimen is being referred 

 to M. t. acholi on a provisional basis. 



M. t. acholi may be distinguished from the subspecies of Mtis 

 hellus occmTing in the same area by its generally larger ear, longer 

 head and body, greater size of M^ greater length of the upper tooth- 

 row, and by the generally larger skull. 



Mus tenellus tenelliis (Thomas) 



Figure 7,d 



Leggada tenclla Thomas, Proc. Zool. Soc. London, pt. 1, p. 298, August 6, 1903. 

 (Roseires, Blue Nile.) 



Specimen Examined: The type only, in BM. 



Measurements: The measurements of the type, an adult female, 

 are as follows: Length of head and body 50; length of tail 35; length 

 of hind foot 11.5; length of ear 8; greatest length of skull 17.2; condy- 

 loincisive length 16.2; length of anterior palatine foramina 3.8; crown 

 length of upper toothrow 2.9; least interorbital width 3.1; width of 

 rostrum at level of antorbital foramen 2.3; length of nasals 6.7; great- 

 est width across zygomatic arches 8.8. 



Remarks: Mus tenellus can usually be distinguished from AIus 

 hellus by its shorter tail and shorter hind foot as well as a generally 

 darker dorsal color and less extensive white on the belly. The skull 

 is usually larger in all respects except the auditory bullae, which are 

 of the same size but appear smaller in consequence of the larger skull. 



Apparently tenellus and its subspecies in the Sudan are not common 

 mice since so few are known in collections. 



Mus triton iniatongensis Setzer 



Mus triton imatongensis Setzer, Journ. Washington Acad. Sci., vol. 43, No. 10, 

 p. 334, October 22, 1953. (Gilo, Imatong Mountains.) 



Specimens Examined: Twenty-one, all from Gilo, Imatong 

 Mountains (9, MCZ). 



Measurements: Average and extremes of seven adult males and 

 four adult females from Gilo are, respectively: Length of head and 

 body 71.5 (66-79), 77.5 (72-81); length of tail 53.5 (50-56), 54 (53- 

 57); length of hind foot 16 (14-17), 16.5 (16-17); length of ear from 

 notch 8.5 (7.0-9.0), 8.6 (8.0-10.0); condyloincisive length of skull 

 19.5 (19.5), ?; greatest width across zygomatic arches 10.5 (10.3- 



