254 
THE MAMMALS OF EGYPT. 
The ears externally and internally are nearly nude, fleshy white in colour, being very 
sparsely covered with short white hairs, but a few more numerous reddish hairs clothe 
the very limited area on the outer side of that part of the inner border that is folded 
over, A number of longish hairs fringe the lower portion of the anterior border 
of the conch, the remainder of the ear being finely fringed with minute hairs, the 
longest of which are at the base of the posterior border. 
The general colour of the upper parts is rich reddish fawn, and of the under parts pure 
white; there is a whitish area below and above and behind the eye, and a pale area 
in front of it, but there is a narrow fawn-coloured streak passing obliquely downwards 
from the eye, separating the white areas at the back and under surface of the eye. 
There is also behind the ear a tuft of nearly pure white hairs. The margins of the 
eyelids and the eye itself are black. The incisors are yellow. 
Measurements taken from specimens preserved in alcohol. 
Gizeh. 
Sakkarah. 
r~ 
d. 
d. 
d. 
$. 
mill. 
mm. 
mm. 
mm. 
Head and body. 
. . 87 
84 
85 
75 
Tail.. . . . 
115 
127 
120 
Hind foot. 
.28 
30 
27 
Ear .. 
13 
13 
11 
Skull-measurements. 
Gizeh. 
t — 
d. 
d. 
d. 
mm. 
mm. 
mm. 
Greatest length. 
28-5 
27 
28 
„ breadth. 
15‘5 
15-1 
15-5 
Least supraorbital constriction . 
5‘5 
5'6 
6 
Length of nasals. 
10-3 
10 
10 
Basal length. 
23-8 
22 
23-8 
Length of incisive foramina . . 
4-8 
4 
4'5 
,, molar series .... 
3-9 
3-8 
3-9 
skull is almost a miniature 
representation 
of that 
of the 
larger species. 
(7. pyramidum, but differs from it in its comparatively greater interorbital breadth 
and in the relatively shorter and somewhat more depressed nasal portion. 
This gerbil inhabits sand-dunes and lives in oolonies. 
Arabic name ‘ Baiyondeh.’ 
