OCR Text |
Show between three species, viz., the Indian Spot-billed, the Wild Duck, and the Pintail (Dajila acuta) ; in each case both the parents being hybrids. In one instance the drake was a Spot-billed Mallard, and the duck a Pintail Mallard, and in the second instance the sexes were reversed. In pointing out in what manner these crosses partook of their parent forms, Mr. Bonhote drew attention to the fact of the great tendency they showed to become white on the underparts, which he was inclined to believe was a sign of reversion to an earlier form, having regard to the numerous species of water-birds in which light-coloured underparts were a constant feature. A water-colour drawing of a male Spot-billed and Mallard hybrid in eclipse plumage was also shown ; and it was pointed out that in the winter plumage this individual closely resembled the Mallard, while in the eclipse plumage it showed greater evidence of the other parent. Mr. Bonhote drew the following conclusions from his experiments, so far as they had at present been carried :- (i) Hybridism between three species of surface-feeding Ducks is comparatively easy of attainment; hybrids between two species showing no evidence of sterility. (ii) There is a marked tendency in the produce towards white underparts. (iii) So far as can be judged, the Pintail is slightly dominant over the Mallard, and the Mallard over the Spot-bill. (iv) The chestnut breast and spotted bill are the most dominant features of their respective species. (v) In a hybrid one species may be dominant in the winter plumage, and the other parent in the eclipse plumage. 1902.] MR. OLDFIELD TnOMAS ON THE BONGO ANTELOPE. 319 Mr. Oldfield Thonms exhibited a mounted male, and a female skull of the East African representative of the Bongo Antelope, recently described by him as Boocercus euryceros isaaci1 on these specimens, which had been obtained by Mr. F. W. Isaac in the deep forest of the Eldoma Ravine, British E. Africa, and presented by him to the National Museum. Mr. Thomas drew special attention to the horns of the female, which, in proportion to the size of the animal, were longer than those of the male. The measurements had been given in the paper describing the subspecies. This was no doubt the animal to which reference had been made by Mr. F. J. Jackson in a letter read before the Society in 1897 2, when the horns of a female were exhibited at the Meeting and figured in the ‘ Proceedings,' although at that date the native statement that they belonged to a female was not credited, and they were supposed to be those of a male Bushbuck allied to the Inyala (Tragelaphus angasi). 1 Ann. Mag. N. H. (7) x. p. 310 (1902). 2 P. Z. S. 1897, p. 455. |