232 MR. R. COLLETT ON HYBRID GROUSE. [Apr. 20. 



The covering of the feet is still thin and incomplete, and the hair- 

 like 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 tile tail and belly, and |)artially 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 Tetraonidae, 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 accu- 

 racy. 



In all the males dissected (in winter) the testes have been found 

 to be small, although not rudimentary or abnormally formed. 

 Their colour was gre\ ish white ; the left was generally larger than 

 the right, and measured in one specimen 5 millim. in lengtli, the 

 breadth about 3 millim. In another, and this towards the spring 

 (28th February), they were unusually small, barely 2 milUm. 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 sjjccies 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 tiie few seconds in which it rises, to fall 



