Descriptive List of the Rodents of South Africa. 221 



and more richly coloured than what may be called the typical race 

 from the neighbourhood of Cape Town. 



Dimensions. As has been remarked by former writers, there is a 

 great variation in the dimensions of this species. In the case of 

 spirit preserved specimens in the South African Museum, the length 

 of the head and body varies from 3-60 to 4-90, and the tails from 

 3'70 to 5-90. The following are the dimensions of an individual 

 measured in the flesh from the neighbourhood of Cape Town : Head 

 and body 4-30 ; tail 4'10 ; hind foot I'O ; from ear to tip of nose '88. 



The dimensions of sub-species bcchuanac measured in the flesh are : 

 Head and body 5 - ; tail 4-62 ; hind foot 1-0. Of sub-species dilectus : 

 Head and body 4-25 ; tail 3'25 ; hind foot '75 ; the dimensions of a 

 typical skull are length 1 - 10, breadth '60 ; upper tooth row -20. 



Distribution. The type of this species was obtained by Sparrman 

 on the banks of the Slangen River, close to Cape St. Francis, in 

 what is now the Humansdorp Division of the Colony ; the species 

 is very common everywhere all over South Africa, and extends 

 northwards to Great Narnaqualand on the west, and through Nyassa- 

 land as far as Mianzini near Lake Naivasha in British East Africa, 

 whence Thomas has described a third sub-species, A. p. dimidiatus, 

 rather smaller and more brightly coloured than the typical one. As 

 already stated, the two other sub-species, A. p. becliuanac and A. p. 

 dilectus, come from Bechuanaland and Mazoe in Mashonaland 

 respectively. 



ARVICANTHIS DORSALIS, THE SINGLE-STRIPED MOUSE. 

 M-iis dorsalis, A. SMITH, Illustr. Zool. S. Air. Mamm., pi. xlvi., 

 fig. 2 (1849) ; BOCAGE, Journ. Sci. Lisbon (2), v., p. 16 (1890). 

 Armcanthis dorsalis, DE WINTON, Proc. Zool. Soc., p. 803 (1896). 



Description. General colour above reddish brown, the fur coarse 

 like that of the other species ; a single median black stripe running 

 from the neck to the root of the tail ; below rusty white ; the skin 

 white, not slaty as in the other species ; ears rather broad, covered 

 with coarse hairs, mingled reddish and black, the former prevailing ; 

 extremities of the same colour as the sides but white inside ; the 

 first and fifth digit of the forelimb very small and rudimentary, the 

 latter provided with a small flat nail, so that the hand bears only three 

 clawed digits ; sole of the hind foot with three well-developed pads 

 only, those at the base of the first and fifth toes and the one next to 

 these proximally being very small or absent. 



Tail longer than the head and body, but in other respects resein- 



