Part 56

Published by R. H. Porter.]

24. THE BLACK-FRONTED DUIKER.

CEPHALOPHUS NIGRIFRONS, GRAY.

Cephalophus nigrifrons, =Gray=, P. Z. S. 1871, p. 578, fig. 6 (skull), pl. xlvi. (animal); =id.= Cat. Rum. B. M. p. 27 (1872); =id.= Hand-l. Rum. B. M. p. 96 (1873); =Peters=, MB. Ak. Berl. 1876, p. 482 (Cameroons); =Scl.= List Anim. Z. S. (8) p. 147 (1883); =Thos.= P. Z. S. 1892, p. 419; =Lyd.= Horns and Hoofs, p. 210 (1893).

Cephalophus aureus, =Gray=, Ann. Mag. N. H. (4) xii. p. 42 (1873) (jr.); =id.= Hand-l. Rum. B. M. p. 95 (1873).

VERNACULAR NAME:--Ngolo in the Cameroons (Buchholz).

Size medium. Colour of body rich chestnut, scarcely or not at all paler below. Centre of face and crest deep black, contrasting markedly with the rufous superciliary streaks. Nape browner. Feet and tip of tail blackish, a few white hairs in the terminal tuft of the latter. Hoofs apparently longer in proportion than usual; lower edge of the posterior outer hoof 1·57 inch in length.

Horns, judging only from the cores, decidedly short, and but little expanded at their base; the cores in an adult male about 1·9 inch long. Their set parallel to, and a little below, the level of the nasal profile.

Skull with the frontal region decidedly convex. Muzzle rather narrow and elongated. Anteorbital fossæ of medium depth. Median posterior palatine notch some distance (⅓ inch in type) in front of the level of the lateral notches.

Dimensions:--♂. Approximate height at withers 19 inches, ear 2·3, hind foot 9·2.

Skull: basal length 6·3 inches, greatest breadth 3·1, muzzle to orbit 3·6.

Hab. Coast of Western Africa from Cameroons to Gaboon.

Although the great wood-region of Western Africa has been repeatedly visited by naturalists since the days of Afzelius in the last century, and many collections have been formed there, very little has been recorded respecting the habits of the mammals of this part of the continent. The reason of this, no doubt, is mainly the impenetrable nature of the forests and bush which cover the whole country and which allow much fewer observations to be made upon the habits and peculiarities of the animals than in the more open and easily traversed districts of the Ethiopian Region. Of the present and several other species of this genus of Antelopes, for example, we shall see that very little information can be given except what results from the examination of their skins and skulls brought home as specimens for our museums.

Skull of Cephalophus nigrifrons.

(P. Z. S. 1871, p. 598.)]

Like Harvey’s Duiker of Eastern Africa, the Black-fronted Duiker, which is its representative and close ally in the great western wood-region, carries a coat of a nearly uniform chestnut. Like C. harveyi, also, it has a distinct black blaze down the centre of the face, whence the appropriate name C. nigrifrons has been bestowed on it. Its distinctions from Harvey’s Duiker, as pointed out by Thomas, are that it is of a much more uniform colour all over and hardly paler below, while in the last-named species the cheeks, sides of the neck, and throat are of a pale bay, and the chin is white as in C. natalensis. Its most striking characteristic is, however, the fact that its hoofs are very much longer than is usual in the genus, an elongation which is probably due to its inhabiting marshy and boggy regions, where its long hoofs would prevent its sinking so deeply as it otherwise would into the muddy soil.

The typical specimens of this Duiker formed part of the collection made by Mr. DuChaillu during his celebrated visit to the Gaboon in 1856 and the following years, the greater part of which were ultimately acquired by the British Museum. On reference to the ‘Explorations and Adventures in Equatorial Africa’ of DuChaillu we can find no reference to it, unless, as is probable, it is alluded to as one of the “four species of Gazelle not yet determined,” which are enumerated in the appendix. When, however, DuChaillu’s specimens came under the experienced eye of the late Dr. Gray, on the occasion of his preparing a monograph of the genus Cephalophus (subsequently published in the Zoological Society’s ‘Proceedings’ for 1871), it was quickly discovered that amongst them was a representative of a new and distinct species of the present genus, which was described and figured as C. nigrifrons. In a subsequent communication to the ‘Annals of Natural History’ in 1871, Dr. Gray described a specimen of what he believed to be another new species of Cephalophus under the name of C. aureus. On this occasion he tells us that the specimens, both of his C. nigrifrons and of his C. aureus, “had been sent home from Africa by Mr. DuChaillu as materials for stuffing out the skin of a specimen” of a larger Antelope (Tragelaphus euryceros). We believe it to be the fact that, as Sclater was assured by the late Dr. Gray, he described four new species of Antelopes from skins found in the interior of this Tragelaphus when it was unstuffed for the purpose of being remounted for the collection of the British Museum. As regards the so-called C. aureus, however, a close examination of the typical specimen, made by Thomas in 1892, convinced him that it was a very young animal and was probably only an immature individual of the present species. We may observe, however, that its body is far brighter and more fulvous than that of the adult, that the withers and shoulders are browner, and that the caudal tuft is more abundantly mixed with white.

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.