264 Mr. 0. Thomas on the Steatorays of Angola, 



XXX. — Note on the Steatomys of Angola. 

 By Oldfield Thomas. 



By the kindness of Prof. Barboza du Bocage the British 

 Museum has received a Large number of the small mammals 

 on which his recent papers on the Mammals of Angola were 

 based, and amongst them are a pair of the animal referred by 

 him * to Steatomys edulis^ or, as it ought to be called, ;S'. pra- 

 tensis f, Peters. In so referring it, however, he remarks on 

 the great difference in size which exists between the Angolan 

 and Mozambique forms — a difference which, on direct compa- 

 rison of specimens from both localities, I am disposed to 

 consider as of fully specific value. This being the case, the 

 Angolan form will need a new specific name, and I cannot 

 apply to it a better one than that of Prof. Bocage himself, 

 whose invaluable papers on the mammals of that country 

 form an epoch in the advancement of our knowledge of 

 African mammalogy. 



Steatomys Bocagei^ sp. n. 



Much larger than S. jivatensis and with a longer tail, but 

 with proportionally rather shorter ears. Skull apparently 

 quite similar in form to that of the Zambesi animal, except 

 that the bullae seem to be rather broader and more flattened 

 and the infraorbital foramina more widely open. The decided 

 difference in size is best shown by the comparative skull- 

 measurements given belov/. 



Dimensions of an adult female in spirit : — 



Head and body 97 millim. ; tail 57 ; hind foot 18'2 ; ear 

 (above crown) 11 "4. 



Skull-dimensions of the above female and of a fully adult 

 specimen of the same sex from Mozambique, collected and 

 determined by Prof. Peters, and which may therefore be 

 looked upon as a co-type of ;S^. pratensis : — 



S. Bocagei. 8, pratensis. 



Basal length 23-9 20-1 



Greatest breadth 13-9 12-0 



Nasals, length ll'O 9-5 



Interorbital breadth 4-0 3-8 



* J. Sci. Lisb. (2) v. p. 17 (1890). 



t MB. Ak. Berl. 184(5, p. 258. In his larger work (Saug. Mossamb. 

 p. 163, 1852) Peters altered the name into S. edulis, but the alteration is, 

 of course, quite invalid. The same remark applies to Saccostomus lapi- 

 darius, Pet. (1852), which ought to stand as *S'. campestris, Pet. (1846J. 



