274 
Annals of the Transvaal Museum. 
Georychus caecutiens Wag. 
5 c?cTj 1 ?, Wilgekuil, Pretoria District (Powell). 
4 Rooikrans, Rustenburg District (Powell). 
These specimens are similar to Georychus specimens from Knysna 
(? caecutiens), in the shape of the nasals, colour, and the presence of an 
inguinal pair of mammae. I may here state that three specimens in the 
South African Museum, Capetown, kindly lent me for comparison by 
Dr. Peringuey, from the Paarl District, differ from Knysna specimens in 
having the nasals shaped as in G. natalensis and in having a yellower 
coloration, matching that of G. rufulus ; the mammae are six in number, 
two pairs pectoral and one pair inguinal. G. natalensis, komatiensis, 
jamesoni, rufulus, arenarius, and jorisseni all have two pectoral pairs of 
mammae, but none inguinal. The occurrence of a species with an inguinal 
pair of mammae so far north is therefore of considerable importance. 
Bathyeryus suillus, B. janetta, and Georychus capensis canescens all have the 
same formula as in G. hottentottus ; but typical specimens of G. capensis 
from the neighbourhood of Capetwn have an extra pair of inguinal 
mammae, or four pairs in all. G. anomalus has three pectoral pairs, but 
no inguinal mammae. When these facts are taken in conjunction with 
some small differences in the skulls and coloration, some surprising results 
are obtained, for it becomes apparent that there is a certain amount of 
homoplasy in their evolution, and we may look for the occurence of more 
than one species in many places. Powell has collected three species in 
the “ bushveld ” region in the neighbourhood of the Crocodile River, 
namely, this Knysna species in marshy flats, G. rufulus on the drier ridges, 
and G. jorisseni where a certain aloe grows in abundance ; and the 
difference between these species in cranial and colour characters is not 
very striking. 
Georychus vryburgensis spec. nov. 
In the Albany Museum there are a number of specimens of a large 
grey-brown species collected at Vryburg, which appear to represent a new 
form, for permission to describe which I am indebted to Mr. J. Hewitt. 
While it is unfortunate that none of the skins with complete skulls are 
adult, even the youngest specimens show the same characters as a very old 
one with only a part of the skull. The most striking character is the thick- 
ening of the arch above the antorbital foramen, otherwise the cranial 
characters are those of G. anomalus enlarged. The largest specimen, 
apparently a very old with only the anterior part of the skull preserved, 
measures: “ head and body 235 mm.; tail 17; hind foot 24”; width of 
the incisors at the base 6 -3 ; width at the base of the premaxilla 9 -2 ; 
molar series 6 -8 ; diastema 15 ; nasals 17 -3 X 4 -3. The type, a young 
adult $, measures : “ head and body 155 ; tail 15 ; hind foot 25 ” ; 
greatest length of skull to the exposed tip of the premaxilla 38 -8 ; to the 
tip of the nasals 35 ; basilar length 32 ; zygomatic width 28 -2 ; width of 
brain case 15 -8 ; mastoid width 19 ; interorbital constriction 7 -8 ; width 
of premaxilla at base 7 *6 ; width of incisors at base 4 *9 ; molar series 7 T ; 
diastema 13 -2 ; length of bullae, diagonally, 11 ; nasals 14 -8 X 4 T. 
