ANATIDJ3— THE SWANS, GEESE, AND DUCKS. 171 



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

 occiput; lower half of the neck, lower parts generally, wing-coverts, secondaries, and outer 

 scapulars pure white, the latter narrowly, and the feathers of the flanks more widely, edged 

 with black; posterior parts of the body beneath tinged with pale ash-gray; upper tail-cov- 

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

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

 length, about 14.50 inches; extent, 24.50; wing, 6.75-6.90; culmen, 1.10-1.15; tarsus, 1.30; 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 lilac-pink, the webs and joints darker. Length, about 12.50 inches; extent, 

 21.00; wing. 5.90-0.00; 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 northward 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 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 gnu dive with the quickness of thought, and often 

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



Genus HISTRIONTCUS Lesson. 



Hiatrionicua Less. Man. ii. 1828, 415. Type, Anaa hiatrionica Linn. 

 Coamone8aa Kaup, Entw. Europ. ThierW. 1829, 16. Same ;ype. 



\,onetta Kaup. 1 c. 196. 

 Phylaconetta Bbandt, .Mem. Ac. 8t. Petersb. \ i. 1849, i. Same type. 



1 1 r.N. < 'iiak. BIosl like Glancionetta. Bill very small (shorter than the tarsus), the lateral 



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



depth of the maxilla at the base about equal to its width ; lamellae entirely hidden by the 

 overhanging inaxiliai'. tomlum; upper basal portion of the maxilla forming a decided 

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

 r farther forward; a Bllghl membranous lobe at the lower base of the 

 me cilia, overhanging the rictus. Tail rather long (more than half the wing), moon gradu- 

 ated, consisting of fourl there. Plumage of the sexes yery different, the male very 

 handsomely marked, the i male very sombre. 



