MAMMALIA. 93. 
Cervicapra Isabellina, Sundevall, Pecora, 70. 
Antilope Eleotragus y. Isabellina, Fischer, Syn. 435. 465. 
Var. 2. With a large black rhombic spot on the back of the head, 
behind the ears; female—Gray in Knowsley Menag. 13. 
Afzelius, Lichtenstem, H. Smith and Sundevall have described 
two species of this genus as coming from South Africa; the 
smaller they call A. Eleotragus, and the larger A. Isabellina. 
The latter author has given a comparative character between the 
two kinds, but he has only seen two specimens of the former (a 
male at Berlin and a female at Stockholm), and several speci- 
mens of the larger kind. I have exammed with care a series 
consisting of four males and five females from different parts of 
South Africa, and can find no distinction between them, except 
a slight difference in the length of the fur and in its colour. Two 
specimens in the British Museum are larger than the rest, and 
have the tarsus one-fourth longer than the others; they have a 
shorter fur and are of a rather brighter colour, and the front of 
the leg is blacker; but the fur and colour probably depend on 
the season when they were killed. In these respects they agree 
with Sundevall’s description of A. Isabellina, but they both have 
the temporal spot large and quite naked, while Prof. Sundevall 
described the spot on this species as pubescent. The female 
of the larger specimen has the black spot on the back of the 
head; some of the smaller ones have the temple-spot much 
smaller and less naked than the others. The two larger speci- 
mens have a single whorl of hair im the middle of the back; the 
others, with longer hair, show the whorls more distinctly, and 
have the hair from the central whorls to the shoulders formmg a 
more or less diverging line. After examining these specimens 
and those in other collections, I conclude that they form only a 
single species. M. Sundevall, in a note just received, observes, 
“Mr. Wahlberg considers A. Isabellina and A. Eleotragus as 
very distinct, and our specimens seem to show a difference, 
though not very well expressed. Also I have committed a mis- 
take, for the young female described in my Synopsis as y. under 
A. Isabellina is really A. Eleotragus.” 
Riet or Reed Bok (Eleotragus) lives in reedy marshes, and in 
the grass of damp flats, in which it lies close until actually put 
up by the hunter or his dogs, and even then rarely running be- 
yond musket range; hence it has been nearly exterminated near 
the colony. 
The Rooye Rhee Bok inhabits the rugged slopes of high moun- 
tains, and the summits of those of less elevation, from the east- 
ern district of the Cape colony to the Tropic of Capricorn, living 
in small herds.—Andrew Smith. 
