1908.] MAMMALS FROM ZAMBESIA. 545 



Peters's " Meriones leitcogaster " (type-locality Mesuril) is a 

 member of the short-tailed group, of which most of the species 

 are found north of the Zambesi. 



21. Arvicanthis dorsalis calidior, subsp. n. 

 $. 1962. 



Comparison of the series from the Zambesi Basin with those 

 from the Transvaal and Zululand, which, as the type shows, 

 represent the true Arvicanthis dorsalis of Smith, establishes the 

 fact that individuals of the former are easily separable by their 

 darker, warmer colouring, and we propose to separate them as a 

 geographical race under the name of Arvicanthis dorsalis calidior. 



Size and fur as in typical A. dorsalis. 



Colour-pattern richer and darker than in the southern form. 

 General colour " chestnut " above, individual haii-s dark slate with 

 " vinaceous cinnamon " band and black tip ; in true A. dorsalis the 

 general aspect is near "clay-colour" and the pale rings of the 

 individual hairs are the palest buff. 



Dimensions of the type : — 



Head and body 135 mm. ; tail 146 ; hind foot 27 ; ear 17. 



Skull — greatest length 34 ; basilar length 27 ; zygomatic 

 breadth 16 ; diastema 8'5 ; upper molar series 6. 



Hah. Zambesi Basin (type from Tambarara, Gorongoza 

 Mountains). 



Type. Old male. B.M. no. 8.1.1.72. Original number 1817. 

 ■Collected 13th March, 1907. 



The present specimen from Tette, though immature, is identi- 

 fiable as belonging to this subspecies, in which also should be 

 included the specimens dealt with in our paper on the collection 

 from Beira (P. Z. S. 1907, p. 779), a series in the Museum 

 Collection from Mashonalancl, collected by Mr. J. ff. Darling, 

 •others presented by Mr. C. F. M. Swynnerton from Chirinda, &c. 



" Native name, ' Mhoni.' 



" Rare in this district, the specimen sent being the only one 

 taken or observed." — C. H. B. G. 



22. Mus MiCRODON Peters. 



S. 1964, 1965, 1966, 1972, 1973, 1983, 1984, 1987, 1988, 

 ■2008. 2 • 1979, 1981, 1990, 1991, 1992. 



Topotypes of species. 



The characters of these specimens prove that the group of 

 South African multimammate mice is divisible into two species. 

 The present one, with a tail equal in length to the head and body 

 combined, extends, so far as we can judge from the specimens 

 available, from jSTatal and Zululand northwards along the coast 

 and throughout the Northern Transvaal and Rhodesia to the 

 Zambesi. The second species, Mits coucha, recognisable by its 

 proportionally much shorter tail, is represented in the Museum 



35* 



