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Show 232 MR. R. COLLETT ON HYBRID GROUSE. [Apr. 20. The covering of the feet is still thin and incomplete, and the hairlike feathers have only appeared on the innermost toe-joint; the claws are brown horn-colour, resembling those of the Blackgame, but their form is more like those of the Willow-Grouse. The change of the young to winter plumage (PI. XXII. fig. 2) proceeds in about the same manner as in the Willow-Grouse; and, analogously with what takes place in them, the first plumage has not always time for development all over before it is dislodged by the winter garb. As already mentioned, the remiges with their longer coverts, the abdomen, and after them the tail-feathers, are the first parts which moult into the winter garb. In the beginning of October the young plumage of the male is half lost, and the winter plumage completed on the tail and belly, and partially on the back, whilst the head, neck, and upper breast are still mottled brown ; one or two brown autumnal feathers are also long retained on the flanks. The covering of the toes is still scanty. The Christiania Museum possesses several such specimens. Sex. As previously mentioned, amongst the twenty-two known specimens from Norway there are but two females. This may partly be for the reason that the hens even in winter plumage have on the whole a less attractive plumage than the males, and therefore might be more easily overlooked, or pass for a white-speckled Greyhen. But the main cause may probably be a different one. It is a well-known fact, confirmed by a majority of instances, that amongst hybrids an unusually large percentage of males are produced. If compared with the other and better known hybrid of the Tetraonidas, the " Rakkel-fugl" (Tetrao tetrix male + Tetrao urogallus female), it will appear that there are perhaps ten males to one female. However, it must be remembered that the female Rakkelfugl is even to a greater extent more likely to be overlooked than the hen of the Rype-Orre, as it exactly resembles a small female Tetrao urogallus, so that this proportion cannot be computed with accuracy. In all the males dissected (in winter) the testes have been found-to be small, although not rudimentary or abnormally formed. Their colour was greyish white; the left was generally larger than the right, and measured in one specimen 5 millim. in length, the breadth about 3 millim. In another, and this towards the spring (28th February), they were unusually small, barely 2 millim. long. In the hens, which were also shot in winter, the ovary was visible on the left side like a small whitish patch ; the eggs were hardly discernible. Supposed Parentage. Which species contributes the father and which the mother to this peculiar hybrid is as yet unknown. Only exceptionally has it fallen to the lot of an intelligent sportsman to see it in its living state, and then only for the few seconds in which it rises, to fall |