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PROCEEDINGS OF THE NATIONAL MUSEUM 



Figure 7, — Distribution of Mastomys (in part), Praomys, and Mmj in the Anglo-Egyptian 

 Sudan. (Scale: 1 inch=400 miles.) 



10.8), 10.8 (10.8); length of nasals 7.9 (7.8-8.1), 8.3 (8.2-8.5); least 

 interorbital width 3.9 (3.9); 3.9 (3.8-4.0); crown length of upper 

 toothrow 3.6 (3.5-3.7), 3.6 (3.5-3.7). 



Remarks: These specimens were all taken in grass either in coffee 

 plantations or along forest streams. The characters separating 

 imatongensis from the nominate form from Uganda are the greater 

 development of the auditory buUae and the vaulting of the cranium. 



Specimens taken in June are somewhat lighter in color than those 

 taken in January, 



