BiEDS OF Indiana. 613 



thinks this may be an escaped hybrid between a Muscovy and a tame 

 duck. Such hybrids are known, and it is not definitely known that 

 any authentic examples of this tropical duck have been taken in the 

 United States, though it is known to occur in Mexico. 



Subfamily FULIGULIN^. 



20. Genus AYTHYA Boie. 



«i. Culmen longer than inner toe with claw; bill not wider toward end than at 

 base ; male with head and neck reddish, 

 i'. Bill much shorter than middle toe without claw ; nail decidedly hooked. 



Subgenus Aythya. 

 C. Bill 2.00 or under, its color dull blue, with blackish band at end ; head 

 and upper neck rich rufous in male. A. aniericaua (Eyt.). 39 



6^. Bill as long as middle toe without claw, flattened at tip; the nail very 

 slightly hooked. Subgenus Aristonetta Baird. 



d'. Bill over 2.00, blackish in color, no band at end ; head and neck red- 

 dish brown ; top of head blackish in male. A. vallisneria (Wils.). 40 

 o^. Culmen as long as outer toe with claw ; bill wider toward end than at base ; 

 male with head and neck black. Subgenus Fuligula Stephens, 

 e'. Speculum white, tipped with black. 

 /'. Flanks white, unspotted. 



.7'. Length 18.00 or over. A. marila nearctica (Stejn.). 41 



p. Flanks white, zigzagged with blackish. 



hK Length under 17.00. A. affinis (Eyt.). 42 



e^. Speculum bluish-gray. 



i^. Wing 8.00 or under. A. collaris (Donov.). 43 



39. (146.) Aythya americana (Eyt.). 



Redhead. 



Adult Male. — Head and upper half of neck rich chestnut red, 

 glossed with reddish-purple; lower neck, chest, upper back, rump and 

 tail coverts (above and below) black; back, scapulars, sides, and -flanks 

 waved or vermiculated with white and black in nearly equal propor- 

 tion; belly immaculate white. Adult Female. — Head and neck gray- 

 ish-broTVTi; darker above; the fore part of the former light; almost 

 white on chin and upper throat; back, scapulars, chest, sides and flanks 

 dull grayish-brown, the feathers tipped with paler or fulvous. 



Length, 17.00-21.00; wing, 8.50-9.35; bill, 2.05-2.35; greatest width 

 of bill, .75-..85. 



Eange. — North America, breeding from California, southern Mich- 

 igan and Maine northward to Fur Countries. "Winters from Virginia 

 to Cuba and Central America. 



Nest, on ground, often on drift like a Coot's. Eggs, 7-14; creamy 

 white; 2.42 by 1.73. 



