_Antilope (Terpone) longiceps_, =Jent.= N. L. M. vii. p. 272, pl. x. (animal) (1885) (_nec_ Gray). _Terpone longiceps_, =Jent.= N. L. M. x. p. 19, pl. i. (horns, ♀) (1887); =id.= Cat. Mamm. Leyd. Mus. (Mus. Pays-Bas, xi.) p. 158 (1892); =Büttik.= Reiseb. a. Liberia, ii. p. 374 (1890). _Cephalophus jentinki_, =Thos.= P. Z. S. 1892, p. 417; =Lyd.= Horns and Hoofs, p. 213 (1893). Size large, though smaller than _C. sylvicultrix_; form stout. Ears short, broad, and rounded. Colour of head, ears, neck all round as far back as the withers, throat, and a narrow sternal line deep uniform black; of body above and beneath coarsely grizzled grey, the hairs ringed with black and white. Lips and chin, a line all round the fore-quarters separating the black from the grey, axillæ, groins, fore and hind legs whitish; a rather darker mark running across the outer side of the forearm. Skull much longer in proportion to the size of the animal than in _C. sylvicultrix_, agreeing, in fact, precisely in size with that of the larger species. In other respects also it agrees so closely with that of _C. sylvicultrix_ that, had the external characters not been known, the two species would have been hardly supposed to be different. Such differences as there are, however, have been fully pointed out in Thomas’s monograph. Horns long, tapering, placed in the line of the nasal profile, divergent as in _C. sylvicultrix_, those of female 6·1 inches long, base not specially thickened, basal diameter going about 5½ times in the length. Dimensions:--♀. Height at withers 30 inches, ear 4, hind foot 12. Skull (♀): basal length 10·5 inches, greatest breadth 5, muzzle to orbit 6·5 _Hab._ Liberia. The present Duiker nearly equals the preceding species in size, but, as will be seen by the Plate, is immediately distinguishable by marked differences in colour, its black head and neck rendering it very conspicuous. Its discovery is due to Mr. F. X. Stampfli, a naturalist who made two expeditions to Liberia, in 1884 and 1886, to collect specimens for the Leyden Museum. In the first of these he was alone; in the second he was accompanied by Mr. Büttikofer, the well-known Conservator of that institution.