We have already mentioned the existence of a living specimen of this Duiker in the Derby Menagerie. Living specimens of it have also been received on more than one occasion by the Zoological Society of London. In 1861 an example was purchased of a dealer in Liverpool and lived more than two years in the Society’s Gardens. A second specimen, quite immature on its arrival, was purchased in February 1866 and was shortly afterwards described by Gray as _Cephalophus breviceps_. This was a female, and, being placed in the same compartment of the Gazelle-sheds as a male of the allied species _C. rufilatus_, bred with it when adult. It produced a young one in January, 1869, and died soon afterwards. A third specimen of the same Antelope was brought home from the Gold Coast and presented to the Society by Mr. C. B. Mosse, Staff-Surgeon, R.N., in October, 1869. This specimen was figured in the Zoological Society’s ‘Proceedings’ for that year (_op. cit._ pi. xlvi.). Mr. Mosse presented another from the same district in 1874. Since that period six other specimens of this Antelope have been acquired at different dates. _May, 1895._ 27. OGILBY’S DUIKER. CEPHALOPHUS OGILBYI, WATERH. [PLATE XVIII. FIG. 2.] _Antilope ogilbyi_, =Waterh.= P. Z. S. 1838, p. 60, 1842, p. 129 (Fernando Po); =id.= Ann. Mag. N. H. (1) ii. p. 472 (1839), xii. p. 57 (1843); =Fraser=, Zool. Typ. pi. xix. (animal) (1849). _Cephalophorus ogilbyi_, =Gray=, Ann. Mag. N. H. x. p. 267 (1842); =id.= List Mamm. B. M. p. 163 (1843). _Antilope (Tragelaphus) ogilbyi_, =Less.= N. Tabl. R. A., Mamm. p. 181 (1842). _Antilope (Cephalophus) ogilbyi_, =Wagn.= Schr. Säug. Suppl. iv. p. 446 (1844), v. p. 423 (1855). _Cephalophus ogilbyi_, =Gray=, Ann. Mag. N. H. (1) xviii. p. 165 (1846); =id.= Knowsl. Men. p. 10, pl. viii. fig. 2 (1850); =id.= P. Z. S. 1850, p. 122; =id.= Cat. Ung. B. M. p. 83 (1852); =Temm.= Esq. Zool. Guin. pp. 194, 217 (1853); =Gerr.= Cat. Bones Mamm. B. M. p. 236 (1862); =Fitz.= SB. Wien, lix. pt. 1, p. 167 (1869); =Gray=, P. Z. S. 1871, p. 595; =id.= Cat. Rum. B. M. p. 26 (1872); =id.= Hand-l. Rum. B. M. p. 98 (1873); =Jent.= N. L. M. x. p. 20 (1887) (Liberia); =Büttikofer=, Reisebild. Liberia, ii. p. 377 (1890); =Matsch.= Arch. f. Nat. 1891, pt. i. p. 353 (Cameroons); =Jent.= Cat. Mamm. Leyd. Mus. (Mus. Pays-Bas, xi.) p. 162 (1892); =Thos.= P. Z. S. 1892, p. 422; =Lyd.= Horns and Hoofs, p. 211 (1893); =Matsch.= MT. deutsch. Schutz-geb. vi. p. 81 (1893). _Sylvicapra ogilbyi_, =Sund.= Pecora, K. Vet.-Ak. Hand-l. 1844, p. 191 (1846); =id.= Hornschuch’s Transl., Arch. Skand. Beitr. ii. p. 143; Reprint, p. 67 (1848).