110 MR. HAROLD SCHWANN ON [Feb. 6, 



20. Leggada mtnutoidbs, Smith. 

 6 . W. 91, 94. Molopo. 



" These mice were taken in the dry bed of the Molopo River, in 

 an old mole run." — H. B. W. 



21. Saccostomus hild^, sp. n. 



J . W. 59, 60, 63, 65. $ . W. 22, 55, 57, 58. Kuruman. 

 A stoutly-built species, probably allied to S. mashon(H de Wint., 

 but smaller and gi-eyer. 



Fur long, thick and very fine in texture, about 13 mm. in 

 length on the middle of back. General colour of upper surface 

 smoke-grey pencilled with black, passing to drab-grey on the 

 flanks. Colour of entire under surface from chin to anus, including 

 fore and hind limbs, pure white, sharply defined laterally. 

 Individual hairs of back slate-colour for basal 10 mm., sub- 

 terminal ring ecru-drab, tips black. Hairs of under surface 

 white to the base, about 8 mm. in length. Tip of muzzle white ; 

 whiskers about 30 mm. in length, black Avith white tips; ears 

 sparsely covered with white hair. Tail short, thick, bicolor, 

 black above, wdiite below. 



Skull smaller than in S. inashonce ; zygomata more expanded 

 antei'iorly, ridges more marked and extending further on to 

 parietals. Antei^o-esternal cusp of m^ intermediate in develop- 

 ment between mashonce and campestris *. 



Dimensions of the type (measured in the flesh) : — Head and 

 body 124 mm. ; tail 51'5 ; hind foot 18-5 ; ear 19. 



Skull : — Greatest length 33*5 ; basilar length 28 ; greatest 

 breadth 17; nasals 1 3*8x4; interorbital breadth 15; breadth of 

 brain-case 13-5; palatilart length 16; diastema 9*10; palatal 

 foramina 6'6 x 2'5 ; upper molar series 4-8. 

 Hab. Kuruman. Alt. 4000 ft. 



Type. Male. B.M. no 4.10.1.49. Original number 63. Col- 

 lected 22nd May, 1904. 



This very well-marked species is distinguishable from aS'. 

 mashonce by its smaller size and generally lighter colour. 



aS'. campestris find fascus Peters are both smaller species. The 

 former was obtained at Tette on the Zambesi, and the latter, 

 the smallest known member of the genus, was taken at Inhambane. 

 iS. lapidarius is synonymous with campestris, Peters having 

 renamed the species, as he considered the former name more 

 suitable. *S'. anderssoni de Wint., discovered in Damaraland, 

 may be distinguished from all other species by its sandy coloration. 

 Specimen number 4.10.1.53 possesses an additional minute 

 molar on each side in the upper jaw behind the usual m\ 

 The teeth in the lower jaw are normal both in size and number. 

 An addition to the molar series of rodents is of such rarity, that 



* De Wint. P. Z. S. 1896, p. 805. 



t Thomas, Proc. Biol. Soc. Wash. vol. xviii. 1905, p. 193. 



