SEA DUCKS. 109 



b. Whole head and throat brown, sharply delined from the gray or white 

 neck; a white patch (speculum) in the wing. 



b^. Nostril nearer the tip than the base of the bill. 



151. Am. Golden-eye $ . 

 b^. Nostril in the middle of the bill . 152. Barrow's Golden-eve 9 . 



c. Whole head and neck black 163. Am. Scoter $ . 



d. A white patch on the top of the head and another on the back of the 

 neck 166. Surf Scoter 6 . 



e. Middle of crown black, bordered by chestnut ; front half of the face 

 white 155. Harlequin Duck i . 



f. Head and neck whitish, grayish, or brownish ; no white in the wing. 

 /I. Bill over 1-25. 



j^. Feathers on culmen reaching much farther forward than those at 



the sides of the bill 166. Surf Scoter 9 . 



/3. Feathers on culmen reaching little if any beyond those at the sides 



of the bill 163. Am. Scoter 9 . 



</i. Bill under 1-25. 

 cj^. Central tail-feathers longest, sharply pointed , under tail-coverts 



white 154. Old Squaw. 



g^. Central tail-feathers not sharply pointed ; under tail-coverts gray- 

 ish brown 155. Harlequin Duck. 



C. Wing under 7-00. 



a. Tail-feathers stiff and narrow ; upper tail-coverts very short. 

 «i. Upper parts mostly rich chestnut-rufous. 



a2. Cheeks white 167. Euddy Duck 3. 



a3. Cheeks black 168. Masked Duck ,3. 



b^. Upper parts grayish or brownish, with sometimes riffous markings. 

 ^2. Lining of wing blackish ; under parts grayish. 



168. Masked Duck 9 . 

 58. Lining of wing whitish^ under parts grayish. 



167. Ruddy Duck 9 . 



b. Tail-feathers normal ; upper tail-coverts about half as long as tail. 



153. BuffleiIead. 

 IL Feathers at sides or top of bill extending forward generally as far as nostril. 



A. Feathers on sides of bill not reaching nostril. 



a. Nostril narrow, elongate ; feathers on culmen extending forward in a 

 narrow line, a V-shaped mark on throat .... 162. King Eider. 



b. Nostril large, rounded; feathers on culmen not extending forward in a 

 narrow line 165. White-winged Scoter. 



B. Feathers on sides of bill extending as far as nostril. 



a. Bare base of bill on top narrow, ending posteriorly in a sharp point. 



159. Greenland Eider. 



b. Bare base of bill on top broad, the posterior end rounded. 



160. Am. Eider. 



The Rufous-crested Duck (I45. Netta rufina) is an Old- World species 

 which has been taken once in America. The record is based on an immature 

 male found in Fulton Market, New York city, which was supposed to have 

 been shot on Long Island. 



