COMMON PTARMIGAN. 197 



Derby, be the Rock Grous, or the Common Ptarmigan, or a species 

 distinct from either, I have seen three specimens in the Museum of 

 the Andersonian Institution of Glasgow, which were purchased from 

 Captain Sabine, and which I think may be referred to the Common 

 Ptarmigan, or at all events are different from the Rock Grous. In the 

 present state of our knowledge as to the changes and variations of plu- 

 mage in Ptarmigans, it is impossible to form a decided opinion in many- 

 instances ; nor will the subject be free of doubt until each alleged spe- 

 cies has been traced through all its gradations. The following is the 

 description of the individual represented in the plate. 



Tetrad lagopus, SaUne (Capt.) Parry's First Voyage, Supplt. p. \91.— Sabine (/.) 

 Franklin's Journal, p. ^82.—Ukhardson, Parry's Second Voyage, Append, p. 350. 



Tetrao (Lagopus) mdtus, the Ptarmigan, Swains, and Richards. Fauna Bor.- 

 Amer. vol. ii. p. 350. 



Adult Male. Plate CCCCXVIII. Fig. 1. 



Bill short, robust ; upper mandible with its dorsal outline curved, 

 the ridge and sides convex, the edges overlapping, the tip declinate, 

 thin edged, rounded ; lower mandible with the angle short and wide, 

 the dorsal line convex, the back broadly convex, the sides rounded, the 

 edges inflected, the tip blunt. Nostrils basal, roundish, concealed by 

 the feathers. 



Head small, ovate ; neck of moderate length ; body full. Feet of 

 ordinary length, robust ; tarsus feathered, as are the toes ; the first toe 

 very small, the middle toe much longer than the lateral, which are 

 nearly equal, the inner being a little longer. Claws slightly arched, 

 depressed, broad, thin-edged, rounded at the end. 



Plumage compact, the feathers ovate and rounded ; those on the 

 tarsi, toes, and soles, oblong, with loose stiffish barbs. Wings rather 

 short, concave ; the primaries strong, narrow, tapering, pointed ; the 

 first an inch and ten-twelfths shorter than the second, which is four- 

 twelfths shorter than the third, the latter being the longest. Tail ra- 

 ther short, nearly even, of sixteen broad feathers, of which the two 

 middle are less strong, but longer than the rest by a quarter of an inch. 



Bill black ; superciliary membrane scarlet ; claws greyish-yellow, 

 dusky toward the base. The plumage is pure white ; but on the head, 

 sides of the neck, and back, are several new feathers which are broadly 



