Annals of the Transvaal Museum, 
271 
Mus deserti (Thos.). 
1 $, Mayville, Pretoria (pres. C. C. Barrett, Esq.). 
1 c£, 1 ?, Mooimeisjesfontein, Rustenburg (Powell). 
1 $, Buffelsdraai, Pretoria District (Powell). 
Mus minutoides umbrata Thos. 
1 $, Lake Chrissie (A. B.). 
Saccostomus campestris Ptrs. 
1 $, Rooikrans, Rustenburg (Powell). 
1 $, Springbokkopjes, Rustenburg (Powell). 
Saccostomus Streeter i mihi. 
4 S'S, 3 $$, Hectorspruit (Streeter). 
Dasymys incomptus Sund. 
2 <y<J, Arnhemburg, Carolina District (A. R.). 
Arvicanthis dorsalis (A. Smith). 
1 <J, Rooikrans, Rustenburg (Powell). 
1 A, Jakalspruit, Rustenburg (Powell). 
Arvicanthis dorsalis calidior Thos. and Wr. 
1 ad., 2 juv., Hectorspruit (Streeter). 
The acquisition of more material from the “ bush veld ” region of 
Pretoria and Rustenburg Districts enables me to separate the races of 
the species, and I find that the specimens from Hectorspruit and Tzaneen 
should be referred on size to A. d. calidior, and those from Boror to A. d. 
rosalia Thos. The long series of skins from Tzaneen shows a certain 
amount of individual variation in colouration, as also do the fewer 
specimens from Hectorspruit ; but, on the whole, they are darker and 
more ferruginous on the hind quarters and root of the tail rhan those from 
Pretoria and Rustenburg. Sir Andrew Smith stated that he found this 
species “ only sparingly within the limits of the colony, but abundantly 
beyond the northern frontier to the north of the Great Orange River.” 
We may, therefore, assume that his type was collected somewhere in the 
western Transvaal and that the three specimens in the Transvaal Museum 
are more or less topo-typical. The following measurements may therefore 
be of assistance in the identification of the South African races : — 
Head and Body. Tail. Hind foot. Ear. 
A. Smith's % 
. . (4"=) 101 
(4" 6'") 113 
(1") 25 
— 
Zoutpan, old $ 
101 
— 
25 
15 
Jakalspruit, old $ 
106 
122 
27 
16 
Hectorspruit, old $ 
125 
140 
26 
15 
Tzaneen, old 
133 
139 
27 
16 
Type: A. d. calidior A.. . 
135 
146 
27 
17 
Boror, old A 
115 
116 
26 
16 
