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Show 1879.] REV. DR. GOODACRE ON THE CHINESE GOOSE. 711 that they do not absolutely render identity of species improbable. Great as may be the difference of general form, is it greater than that between a Carrier and a Tumbler Pigeon, or between a Greyhound and a Pug among Dogs ? As to voice, the Call Duck, Trumpeter Pigeon, and Common Dog all afford instances of modification of voice in a greater or less degree, from the normal voice of the Wild Duck and Rock-Dove in the first two cases, while the bark of the Dog is said to be a domestic accomplishment altogether, but is never supposed to divide Dogs into two species, those that bark and those that cannot; for the young of the latter learn to bark in this country. As to colour, it should be borne in mind that sandy-coloured Geese are not infrequent in some parts. The stripe down the back of the neck of the Chinese Goose is a very distinctive marking ; but it may well be asked if it is necessarily of greater value as a specific distinction than the spinal stripe in certain Horses, especially those of a dun colour. The knob on the base of the bill of the Chinese bird is doubtless the greatest distinguishing mark between the two forms. In the opinion of most naturalists, the Grey-lag Goose is the wild original of our common domestic bird; and from Yarrell we learn that its range extends to China and Japan. The same author also points out its clear grey shoulder as a characteristic of the Grey-lag, distinguishing it from the most nearly allied British wild Geese; and, curiously enough, this is very evident in the Chinese bird. The trachea of the male in most Swans, Geese, Ducks, and Mergansers is a most trustworthy guide as to specific difference: but in the case under consideration it appears to be of little use ; for there is good ground for suspecting that the form of the trachea in the Grey-lag is not constant. Yarrell says:-" In the wild Grey-legged Goose the tube of the windpipe is nearly cylindrical; and this form of trachea I have frequently found on examination of domestic Geese intended for the table ; but I have frequently also found the tube flattened at the lower portion" (Yarrell's Brit. Birds, vol. iii. p. 55). The tracheae of two Chinese Ganders which I have myself examined were very slightly swelled and flattened at the lower portion. I have not had the opportunity yet of examining that of a Chinese Goose; the windpipes taken from cross-bred birds condemned for the kitchen, without regard to sex, have all had a very decided swelling and flattening of the lower portion of the tube. In Chinese Geese there is generally a small rim of white feathers at the base of the bill; and a broader band is far from uncommon in the ordinary Domestic Goose. This and the swelled and flattened trachea have been rightly looked upon as analogous variations ; but perhaps the cause of their occurrence has been too readily accounted for by Yarrell and others by supposing an admixture of blood from the " White-faced Goose" in the building-up of the domestic form in remote times. May it not be that there is a tendency in the Grey-lag to vary in these directions, and that hence such a tendency reveals itself also in the Chinese form ? It may, I know, be asked, If the Chinese form was modified out PROC. ZOOL. Soc-1879, No. XLVI. 46 |