102 RIVER DUCKS. 



the feathers with internal rings or loops and sometimes borders of pale ochra- 

 ceous buffy ; speculum as in the preceding ; breast and belly ochraceous bully, 

 mottled with dusky grayish brown. L., 23-00; W., 11-00; Tar., 1'75; B., 2-25. 



Range. Northern parts of the northern hemisphere ; in America breeds 

 in the interior from Indiana and Iowa, and on the Atlantic coast rarely south 

 of Labrador, northward to the arctic regions ; winters from southern Kansas 

 and Delaware southward to Central America and' the island of Granada. 



Washington, common W. V. Long Island, uncommon T. V., Sept. to Apl. 

 Sing Sing, rare T. V., Oct., Mch. 



Eggs, $ix to ten, pale greenish or bluish white, 2*30 x 1-70. 



The Mallard is far more common in the interior than on the coasts. 

 Its loud, sonorous quack is not distinguishable from that of its domes- 

 ticated descendants. 



133. Anas obscura Gmel. BLACK DUCK; DUSKY DUCK. Ad. 

 Top of the head rich fuscous, slightly streaked with pale buffy ; sides of the 

 head and throat pale buffy, thickly streaked with blackish ; rest of under parts 

 fuscous brown, the feathers all bordered by ochraceous-buff; back slightly 

 darker and narrowly margined with buffy ; speculum rich purple, bordered 

 by black. L., 22-00; W., 11-00; Tar., 1-75; B., 2-20. 



Remarks. Always to be distinguished from the Mallard by the lack of 

 white in the wing. 



Range. North America; breeds from Illinois and New Jersey to Hudson 

 Bay and Labrador; winters southward to the Greater Antilles. 



Washington, common W. V. Long Island, abundant W. V., Sept. to May ; 

 a few breed. Sing Sing, tolerably common S. K., Mch. 6 to Nov. 13. Cam- 

 bridge, very common T. V., Mch. and Apl ; late Aug. to Nov. ; a few breed. 



Efffjs, eight to twelve, pale greenish or bluish white, or creamy buff, 

 2-43 x 1-75. 



This species resembles the Mallard in general habits, and the voices 

 of the two are indistinguishable. The Black Duck, however, is com- 

 moner near the seacoasts, and when molested will sometimes pass the 

 day at sea, returning at night to feed in the marshes and ponds near 

 the shore. 



134. Anas ftilvigula Ridyw. FLORIDA DUCK. Ad. Top of head 

 streaked with black and buffy ; sides of the head and entire throat butty, 

 without streaks ; rest of under parts rich buffy ochraceous, widely streaked 

 with black ; back black, the feathers broadly margined and sometimes inter- 

 nally striped with ochraceous-buff; speculum rich purple bordered by black ; 

 bill olive-yellow, its nail black. L., 20-00; W., 10-50; Tar., 1-6,5; B., 2-05. 



Remarks. Easily distinguished from A. obscura by the absence of streaks 

 on the throat. 



Range. Florida and Gulf coast to Louisiana. 



AV/yx, right to ten, pale dull buffer pale grayish buff, 2-15 x 1-61 (TCidgw.). 



This is a common resident species in Florida. Its habits and voice 

 are practically the same as those of the Black Duck. 



