TETBA ONIDJE — TETBA ONINJE : GROUSE. 



587 



569 



secreting part of the passage is as if covered vvitli fresh paint, S(jft and sticky, which may be 

 rubbed off before it " sets '' on the sliell. Size l.SO X 1-20. 



L. rupes'tris. (Lat. rupestris, relating to nqvis, a rock ; riiiiestrine.) KoCK I'taiimigan. 

 Bill slenderer for its lengtli tlnin that of L. albus, its depth at base less than the distance from 

 nasal fossa to tip; whcde culmen 0.67; bill always black. (^ 9 , ^^ winter: As in L. albus, 

 but a black transocular .stripe on side of head. <? ? , in summer : Thc^ whole plumage, excepting 

 the wings and tail, barred with blackish-brown and brownish-yellow. Katlier smaller than the 



Fig. 404 — Willow Ptarmigan, winter plumage, \ nat. size. (Fioiu Brebm.) 



foregoing. Length 14.00-15.00; wing 7.00-7.50 ; tail 4.50. Arctic America, not S. to the 

 U. S. Eggs 13-15 or more, like those of L, albus, but darker and rather smaller ; size 

 1.70 X 1.18. "The summer plumage is assumed at variable periods of the months of April, 

 May, and even in early June, according to the locality. The moult f(jr the summer is usually 

 shown first on the head and neck, followed by the lower back, sides, breast, middle back, flanks, 

 and abdomen, in the order named. The abdomen and chin are the last areas to sliow the com- 

 plete moult. The parts named also assume, in the order given, the white winter plumage. 

 During the time of the summer plumage scarcely a single day passes that the general color of 

 the feathers is not modified by the appearance or loss of some feather." (Turner.) Hence the 

 difficulty if not impossibility of esta1)lisliing races of this species upon c(dor, as the amount of 

 barring, vermiculation, or nebulation with dusky, tawny, and gray is incessantly changing in 



