1905.] HYBRIDS AMONG NORWEGIAN BIRDS. 25 



crown is barred with a whitish colour and black (L. mutus), 

 but the nape is more red-brown (L. lagopus). 



The entire upper surface with numerous light and dark ver- 

 miculations, in pattern like those of an old male L. lagopus in 

 autumn plumage; but the majority of the light cross bands are 

 of a whitish colour, quite unlike those in L. lagopus, so that 

 the tone is more like that in L. mutus. Heie and there, how- 

 ever, a feather may be found that is brown and black in colour, 

 very much as in L. lagopus. 



On the rump and the upper tail-coverts, the light cross-bars 

 are of the same whitish colour as on the back (L. mutus), 

 whereas the bars are almost of the same (great) width as in 

 L. lagopus. 



On the belly, the colour of the breast is tåken mainlyfrom 

 L. mutus, that of the sides from L. lagopus, while on the ab- 

 domen itself, the colours are almost equally mingled. 



On the breast, as also on the back, the light cross-bars on 

 the feathers are for the most part greyish white (L. mutus); 

 but above and at the sides of this grey breast-region, a few 

 feathers are found with broad black cross-bars upon a red-brown 

 ground, almost as in an old female of L. lagopus in autumn 

 plumage. 



The feathers on the flanks and the abdomen have broad 

 black cross-bars on a pale reddish grey ground. On some of 

 the flank-feathers and a few of the under tail-coverts, the colour 

 of the ground on the one web (the outer), is a reddish grey 

 (L. lagopus), on the other (the inner) whitish (L. mutus). 



Parentage. Concerning the sex of the two parents, no 

 well-founded opinion can be advanced. I have never yet heard 

 of an instance in which the two species have been observed in 

 copulation. 



In the only two Tetraonid hybrids of which the parentage 

 is ascertained, namely, the „Rakkelhane" (p. 6) and the „Rype- 

 Orre" (p. 16), the plumage as a whole, and more especially the 

 colour of the head, neck and tail, are in accordance rather with 



