356 



NORTHERN ZOOLOGY. 



of fourteen black feathers, with the white tips worn off, and of two central incumbent 

 feathers, which, with the adjoining coverts, are barred like the back. Tarsal feathers very 

 short ; the toes naked beneath, and partially so above. — No summer specimens of the 

 male were brought home ; but that sex differs in having the black eye stripe, and in the 

 middle of the belly being white. 









Dimensions 

















Of the summer female. 













Inch. 



Lin. 



Inch. 



Lin. 





Inch. 



Lin. 



Length, total . 



. 14 







Length of bill to rictus . 1 







Length of middle nail 



. 



8 



„ of tail . 



. 4 







,, of tarsus . . 1 



H 



„ of hind toe . 







J| 



,, of wing 



. 7 







,, of middle toe . 1 







,, of its nail 



. 



4 



„ of bill above 



. 



7 













— R. 



[129.] 8. Tetrao (Lagopus) leucurus. (Swains.) White-tailed Grouse. 



Genus, Tetrao, Linn. Swains. Sub-genus (2), Lagopus, Ray. 



Ch. Sp. Tetrao {Lagopus') leucurus hyerne albus : testate variegatus, rectricibus semper albis. 

 Sp. Ch. White-tailed Grouse, in winter entirely white ; in summer coloured : the tail white. 



Plate lxiii. 



Of this undescribed species I have only five specimens, four procured by Mr. 

 Drummond on the Rocky Mountains, in the fifty-fourth parallel, and one by 

 Mr. Macpherson on the same chain, nine degrees of latitude farther north. Mr. 

 Douglas killed several in 1827, but, through the want of means of carriage, was 

 obliged to leave them behind. It is said to have the habits of the Ptarmigan, 

 and to inhabit the snowy peaks near the mouth of the Columbia as well as the 

 lofty ridges of the Rocky Mountains. Its summer dress is intermediate in colour 

 between that of T. lagopus and rupestris ; but it differs from both these species 

 in its smaller size and in its tail being totally white at all seasons. The sexes 

 of my specimens were not noted ; but none of them have the black eye stripe ; 

 and Mr. Dummond, who killed great numbers, is confident that that mark does 

 not exist in either sex. 



