ANATID^— THE SWANS, GEESE, AND DUCKS. 171 



of pure white on the side of the head, extending from the eye backward to and around the 

 ooolput; lower half of the neek, lower parts generally, wing-ooverts, secondaries, and outer 

 scapulars pure white, the latlter narrowly, and the feathers of the flanks more widelr. edged 

 with blaok; posterior parts of the body beneath tinged with pale ash-gray; upper tail-oov- 

 erts light hoary gray ; tail slate-gray, the shafts blaok. Bill bluish plumbeous, dusky on the 

 nail and at base ; iris very dark brown; legs and feet pinkish, or lilaoeous, white. Total 

 length, about 14. 50 inches; extent. 24.60; wing, 6.75-6.90; culmen, 1.10^1.15; tarsus, l.SO; mid- 

 dle toe, 1.90-2.00. Adult female: Head, neck, and upper parts generally dusky grayish 

 brown; an oblong or somewhat ovate white longitudinal patch on the auricular region, 

 and the inner secondaries (sometimes also the greater wing-coverts, except at ends), white ; 

 lower parts white, tinged with brownish gray posteriorly, anteriorly, and laterally. Bill 

 dusky, inclining to plumbeous at end and along commissure; iris very dark brown; legs 

 and toes dilute lilao-plnk, the webs and joints darker. Length, about 12.50 inches; extent, 

 21.00; wing.S.90-6.00; culmen, .95-1.00 ; tarsus, 1.15-1.20 ; middle toe, 1.75. 



There is very little variation among the males of this species. 

 The females vary in the markings of the wing, some having the 

 greater coverts white, tipped with dusky; while in others only 

 the inner secondaries are white. 



This very beautiful little duck is a winter resident in the 

 southern portions of Illinois, its summer home being chiefly to 

 the northwa.rd of the United States. Audubon "met with it, 

 during extremely cold weather, on the Ohio, when the river was 

 thickly covered with floating ice, among i which it was seen 

 diving, almost constantly, in search of food. When the river 

 was frozen over, these birds sought the headwaters of rapid 

 streams, and in their turbulent eddies found an abundance of 

 food. Apparently feeling secure in the rapidity with which they 

 can dive, they allow a very near approach; but at the first 

 snap of the gun dive with the quickness of thought, and often 

 as quickly rise again within a few yards of the same spot." 



Genus HISTMOinCXJS Lesson. 



Histrionicus Lbss. Man. ii. 1828, 415. Type, Anas Mstrionica LINK. 

 Cosrkonessa Kaup, Entw. Europ. Thierw. 1829, 46. Same type. 

 Cosmonetta Kaup. 1. c, 196. 

 Phylaconetta Bbandt, Mem. Ao. St. Petersb. vi, 1849, 4. Same type. 



Gbn. Ohab. Most like Glaucionetta. Bill very small (shorter than the tarsus), the lateral 

 outlines converging rapidly to the tip, which is occupied entirely by the very large nail; 

 depthof the maxilla at the base about equal to its width; lamellae entitely hidden by the 

 overhanging maxillary tomium; upper basal portion of the maxilla forming a decided 

 angle, inserted between the feathering of ithe forehead and that of the lores, the former 

 reaching rather farther forward; a slight membranous lobe at the lower base of the 

 maxilla, overhanging the riotus. Tail rather long (more than half the wing), much gradu- 

 ated, consisting off ourteon feathers. PlVimage of the sexes very different, the male very 

 bandsomely marked, the t. male very sombre. 



