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Show 808 ON SOME RODENTS FROM BRITISH SOUTH AFRICA. [Nov. 17, underside including the upper lip and feet, pure white, line sharply defined; ears and tail brown, naked, the latter paler on the underside. Type, N o . 33, tf, Essex Farm, Matabeleland; 8 Oct., 1895. General colour much like Mus sylvatlcus, but with the smoky bloom peculiar to the genus. Skull, old male:-Greatest length 25-5 ; br. zyg. 12-5 ; br. brain-case 11-3; nasals 10-5x3; interpar. 3 x 8 - 5 ; basal length 21; bk. of ins. to bk. of pal. 12-5; pal. to foram. mag. 7; ins. foram. 5-8; upper molar series 4; outside TOOA 1-6; inside m- 1 3-1; diastema 6-5. Mandible: gr. length (bone) 13-1; to tip of incisors 16. Near A. tvilsoni, Thos., but larger. 8. GEORYCHUS NIMRODI, sp. n. 4 skins, 1 ad., 3 juv.; 5 skulls, 2 ad., 3 juv. All taken in Nov. Size much as in G. hottentottus, Less., and G. darlingi, Thos.: differing from the former in its drab colouring, and from the latter in the absence of the triangular white patch on the nape. The skull is at once distinguished from its allies by the ascending processes of the premaxillaries not extending backward beyond the nasals, so that the suture between these bones and the frontals forms a simple slightly bowed line, very distinct from the complicated dove-tail pattern found in most of the Georychi. The sagittal crest is only faintly developed, the interparietal bone being rounded. The zygomata are not so much bowed out anteriorly as in G. hottentottus,'and in this it resembles G. darlingi, as also in the' thickened outer walls to the anteorbital foramina. In tbe type specimen these foramina are very small, on one side indeed being little more than a pin-hole, but this is a somewhat variable character in this species. From the lachrymal projection the skull recedes abruptly to the narrowest part of the constriction, with no posterior lateral inflation of the frontals in the interorbital region. The postnarial aperture is rather wide, the back of the palate being slightly cut away on either side, leaving a projecting point in the middle line; the posterior opening of the alisphenoid canal is larger than in G. hottentottus. I select as the type a specimen marked by the collector, " JNo. 46, Mole, d, caught 18 Nov., 1895. Head and body 147 mm., hmd foot 24-5. Kaffir garden, only appeared on surface since ramy season began. Locality, Essex Farm, Matabeleland."-^. C. S. Measurements of skull of type: basilar length 31; greatest breadth 27. . This new species is unquestionably nearly related to G. darlingi, but outwardly as well as craniologically the two forms are easily distinguished. |
