In 1882, as recorded in the eighth edition of their ‘List of Animals,’ the Zoological Society acquired by purchase of Mr. Cross, of Liverpool, a living specimen of the Black-fronted Antelope, which lived for about three months in the Menagerie. Of this it can only be said that, like most of the smaller Antelopes (if we except the Gazelles), it was shy and inoffensive in its disposition. The existence of _C. nigrifrons_ in the Cameroons has been recorded by Peters, who published in 1876 an account of the collection of Mammals made by Dr. Reinhold Buchholz in this and other localities in Western Africa. Buchholz, when at the Cameroons, obtained a specimen of the Black-fronted Duiker from the natives who had captured it alive when swimming across a river. He remarks on the prominent appearance of the inguinal glands, and says that the horns are very short and conical, and almost covered by the frontal hairs. The native name of these _Cephalophi_ in the Cameroons is said to be “Ngolo.” Our figure of this Bush-Duiker (Plate XVIII. fig. 1) was prepared by Mr. Smit under the direction of the late Sir Victor Brooke. It was probably taken from the specimen in the British Museum, but of this we are not quite sure. _May, 1895._ 25. THE WHITE-BELLIED DUIKER. CEPHALOPHUS LEUCOGASTER, GRAY. _Cephalophus leucogaster_, =Gray=, Ann. Mag. N. H. (4) xii. p. 43 (1873); =Thos.= P. Z. S. 1892, p. 420; =Lyd.= Horns and Hoofs, p. 211 (1893). Size medium. General colour dull chestnut-rufous, with a black dorsal band. Face rufous, darker down the centre; crest mixed rufous and black. Nape browner. Dorsal stripe commencing in front of the withers, not pure black, but grizzled with rufous, and not at all sharply defined laterally; posteriorly, however, on the tail it becomes abruptly very narrow and sharply defined, not covering the whole breadth of the tail, but bordered on each side with rufous or white. End of tail with a large mixed black and white tuft. Under surface of body from chin to anus, inner sides of forearms and hips, and also a line passing down the anterior side of the metatarsi, whitish or pure white; no trace of a darker sternal patch. Posterior faces of buttocks also pure white, very different from the deep chestnut of this part in _C. dorsalis_. Horns of type (apparently ♀) conical, sharply pointed. Skull, so far as can be gathered from a young and very imperfect example, with a slender narrow muzzle like that of _C. dorsalis castaneus_, quite unlike the short conical one of _C. d. typicus_. Dimensions of the type (an immature specimen):--Height at withers 15 inches, ear 2·5, hind foot 7·9. _Hab._ Gaboon.