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Show 1878.] TRACHEA OF RHYNCHJ-EV CAPENSIS. 747 endowed of the two sexes ; but to this there are a few interesting and remarkable exceptions (Phalaropus, Casuarius, Dromceus, Milvago, Climacteris, Eurostopodus, and the Rhynchseas), of which the last, the ones we are here concerned with, are not the least conspicuous. In these birds in general, and in the Painted Snipes in particular, it may be taken as established that we have, to use the words of Mr. Darwin, a complete reversal not only of the secondary sexual characters, but also of the parental and incubating instincts-the females being not only larger and much more richly coloured than the males1, but having the trachea more or less tortuous instead of straight and simple, deputing the duty of incubation to the other sex, and reserving the business of courting to themselves. In Bhynchcea australis, according to Gould2, the trachea, which is simple in the males, in the females passes down between the skin and the muscles of the breast for the whole length of the body, making four distinct convolutions before entering the lungs; but Mr. Darwin states, on the authority of Blyth, who had examined many specimens, that "it is not convoluted in either sex in Bh. bengalensis, which species resembles B. australis so closely that it can hardly be distinguished except by its shorter toes." This is the statement which seemed to me to stand in need of corroboration, especially when I called to mind the peculiar call of the female3 and the sharp squeak jerked out only at long and irregular intervals by the male, and then apparently only in answer to the female. On opening the necks of the two birds by a longitudinal incision extending to the middle of the breast or thereabouts, and carefully turning aside the skin on either hand so as not to disturb the natural relations of the underlying parts, I found that the trachea of the adult male (ascertained to be such by subsequent examination of the genital organs) was straight and simple throughout, whilst that of the female had a distinct loop lying between the integument and the interclavicular membrane on the left side, and was not only an absolutely but apparently also a relatively stouter tube than that of the male. As the contrary of what I have found has been stated by so good and usually trustworthy an observer as Mr. Blyth, I put in evidence two sketches (figs. 1 and 2, p. 748) showing the course of the trachea in the two sexes. For these sketches I am indebted to Col. Godwin- Austen, who was with me at the time. The numerous birds belonging to this species examined by me may be divided according to sex and age into the following groups:- 1. Adult and probably old females, remarkable for the extreme richness of their plumage. In all the birds of this group which 1 Jerdon, ' Birds of India,' vol. iii. p. 677. 2 'Handbook to tbe Birds of Australia,' vol. ii. p. 275. 3 Of R. australis J. Gould says (op. cit. p. 276), " The use of this convoluted trachea, so exclusively confined to the female, I could not in any way discover or surmise; no note whatever was heard to proceed from either sex whilo on the wing or when flushed "-times at which a call such as that of the female of B capensis, like the coo of a dove, would be least likely to be heard. |