Duck-sbooting 191 



water, and are very rarely found in large flocks. 

 Many of them breed in holes in trees, others lay- 

 ing on the ground, under bushes, and close to the 

 shore. Occasionally they breed in colonies. Like 

 the ducks many of the male mergansers wear for 

 a few weeks in summer a plumage resembling 

 that of the female. 



An interesting genus of this family inhabits the 

 swift mountain torrents of the highest Andes 

 from Columbia to Chili, and can swim and dive 

 with great rapidity against the fast-rushing water. 

 Their bills are more like that of a duck than those 

 of the other mergansers, and they have a large 

 and sharp spur on the wing. On account of their 

 habits these birds are known as the torrent ducks. 



AMERICAN MERGANSER 

 (^Merganser americanus) 



Adult male — Head and upper part of neck, dark, glossy green; 

 feathers on nape elongated ; back and inner scapulars, jet-black ; 

 rump, upper tail-coverts, and tail, ashy gray ; sides of crissum 

 and femoral region, whitish, narrowly barred with slate color ; 

 neck, white ; breast and under parts, fine salmon color, fading 

 to white in dried skins ; primaries, black ; secondaries, white, 

 edged with black ; lesser wing-coverts, black proximally, white 

 distally ; inner greater coverts, black, outer, white ; base of 

 greater coverts, black, forming a bar halfway across the wing ; 

 bill, vermilion, with culmen and nail, black ; feet, vermilion ; 

 iris, red, or reddish brown. 



Measurements — Length, 27 inches; wing, 11 to 11.25 inches; cul- 

 men, 2 inches ; tarsus, 1.90 inches. 



Adult female — Head, neck, and occipital crest, reddish brown ; chin 

 and throat, white ; upper parts, gray, edged with paler and with 



