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Show 1871.] MR. NEWTON ON A SEXUAL PECULIARITY IN A DUCK. 649 8. On a remarkable Sexual Peculiarity in an Australian Species of Duck. By ALFRED NEWTON, M.A., F.R.S., V.P.Z.S. [Received November 6, 1871.] It is now getting on for nearly a year since I received from the Secretary the bodies of two Australian Ducks which had recently died in our Gardens. The species to which they belong is that known as "Anas punctata, Cuvier" * - a name I take as given, not having satisfied myself that it is one which ought to be used. The specimens, the skins of which I now exhibit, were in the diverse plumage which has been fully described as characterizing the two sexes ; and I confess that from such knowledge as I had of the internal structure of the section of the family Anatidee to which this species obviously belongs I never anticipated finding any thing sufficiently novel in the present case to justify me in bringing it to the notice of the Society. How agreeably disappointed I was will be seen. Being much engaged by other occupations, and, as I have said, not expecting any remarkable feature to be presented, I sent the specimens to Mr. Baker of Cambridge, requesting him to skin them, ascertain the sex of each, and prepare the sternums and tracheas. This he did ; and when I add that I have known Mr. Baker for more than twenty years to be a man on whom I can fully rely, I trust no suspicion of the possibility of error may cross the minds of zoologists in consequence of m y not having myself made the dissections. The sternum of every species of freshwater Duck that I have previously seen presents at its posterior end a deep fissure on either side; but this fissure is occasionally so much bridged across by the prolongation of its inner margin in an outward direction that I have been fully prepared to find the junction completed in some specimen, either as a characteristic of the species, as it is in some of the diving Ducks, or even as au individual peculiarity. I was therefore not much surprised to see complete fenestration effected in one of the * Two perfectly distinct species have had the name Anas punctata applied to them-the subject of this notice, and one from South Africa described by Burchell in 1822 (Travels, &c. i. p. 283, note). The earliest publication I can find of "Anas punctata, Cuv.," is by Mr. G. R. Gray in 1844 (List of &c. Anseres, p. 134); but whence he obtained the information he cannot, as he kindly tells me, recollect. Lesson in 1831 (Tr. d'Orn. p. 634) has an "Anas punctata, Gal. de Paris," which, though he suggests it may be one of Horsfield's species, is probably the same as the one meant by M r. Gray, since Dr. Pucheran (R. Z. 1850, p. 549) has identified the specimen which bore that name in the Paris Museum with the Australian species figured under the same designation by Mr. Gould (B. Austral, vii. pl. ). In Dr. Hartlaub's 'Index' to Dr. Pucheran's valuable paper (J. f. 0.1855, p. 419) notice of this case is unfortunately omitted. Unless it can be shown that Cuvier's name was published before Burchell's (and this is extremely unlikely), punctata must of course be kept for the South-African bird, with which (as Mr. Gray has suggested to me) Sir Andrew Smith's subsequently designated Querquedula hottentotta (Zool. S. Afr. Aves, pl. 105) seems to be identical; and the Australian bird will take up with its next synonym- standing then as Anas castanea (Eyton). |