432 RASORES. PERDTX. 



Spring and In spring the plumage becomes varied on the upper anil 

 plumage. under parts with black and deep ochreous yellow ; but 



the quills, through all its changes, remain white, and 

 their shafts invariably black. Towards autumn tlie 

 ochreous-yellow gives place * to a greyish- white ; and 

 the black spots (which in the spring are large and dis- 

 tinct) become broken, and assume the appearance of 

 zig-zag lines and specks. These again, as the season 

 advances, give place to the pure immaculate plumage, 

 which distinguishes both sexes during the winter. 



Genus PERDIX, Lath. PARTRIDGE. 



GENERIC CHARACTERS. 



Bill short, strong, naked at the base ; upper mandible con- 

 vex, with the point bending considerably downwards. Nos- 

 trils basal, and lateral ; pierced in a large membrane, and 

 partly concealed by an arched naked scale. Wings short, 

 and concave ; the three first quills shorter than the fourth 

 and fifth, which are the longest. Tail of fourteen or eighteen 

 feathers, short, and generally bending towards the ground. 

 Feet with three toes before, united by a membrane as far as 

 the first articulation, and with one hind-toe. Tarsus, in the 

 male bird, frequently furnished with one, or more than one, 

 spur or tubercle. 



This genus was first established by Latham, who very 



• Mr Ross, gunsmith in Edinburgh, (who, as a preserver of animals, 

 has had hundreds of Ptarmigans through his hands, and at all seasons of 

 the year) assures me, that he never met with an individual that had not 

 young (or imperfect) feathers on some part of the body. This fact would 

 imply, that the moulting of the Ptarmigan (and perhaps of other alpine 

 birds, or such as live in high latitudes) is different from the usual course, 

 in being constant and progressive, instead of the plumage undergoing a 

 total change at a particular season. May not this be a wise provision, 

 that such birds shall not be too much exposed at any given time, as would 

 be the result of an entire renewal of plumage ? 



