957 

 Subfamily. Sterninae. Terns. 



All of the Terns treated here have forked tails. They usually carry the head at a sharp angle to 

 the line of the body, thus having something of the appearance of a huge mosquito. .\11 are beneficial. 



I. Length about 21 inches. H. 44. Caspian Tern. 



II. Length about 10 inches. 303. Black Tern. 



III. Length alx)ut 15 inches. 



A. Tail forked for only 1.5 inches. H. 43. Gull-billed Tern. 



B. Tail forked for more than ,5 inches. 



1. Entire bill coral red. 302. Arctic Tern. 



2. Bill blackish at tip. 



a. Inner web of outer tail feather dusky. 300. Forster's Tern. 



b. Outer web nf outer tail feather dusky. 301. Common Tern. 



Order 12. AXSERES. Ducks. Geese. Swans. 



There is but a single family within this order, the .■\x.\tid.-\e. but the group is divided into five sub- 

 families, as follows : 



Subfamily i. Merginae. Mergansers, Fish Ducks, 



These are known by the slender cylindrical bill. The two larger species eat fish almost wholly 

 so are not good to eat. The Hooded eats a good deal of .other food, and its flesh is more savory. 



I. Length under 18 inches; a conspicuous hood. 306. Hooded Merganser. 



II. Length over 21 inches. 



A. Head and throat black. 

 I. L'nderparts white, tinged with salmon. 304. American Merganser. 

 J. Breast brownish, heavily streaked with black. 305. Red-breasted Merganser. 



B. Head and sides of neck rufous-brown. 304. American Merganser. 



C. Head and sides of neck grayish brown. 305. Red=breasted Merganser. 



and 



Siibfamilx 



.A.\.\Ti.\AE. River and Pond Ducks, 



These birds are popularly known as "tip-ups." from the 

 tipping the head down beneath the water while the tail s 

 largely vegetation, and their flesh therefore savory. 



I. Length under 17 inches. 



A. Lesser wing coverts green. 



B. Lesser wing coverts blue. 



1. Prevailing color reddish brown. 



2. Prevailing color pattern mottled. 



a. A white crescent in front of the ej'e. 



b. L'nderparts suffused with rusty brown. 



c. L'nderparts sufifnsed with rusty gray. 



II. Length over 18 inches. 

 A. Belly not conspicuously streaked or spotted. 



ir habit of feeding in shallow water and 

 ticks straight up in the air. Their food is 



310. Oreen=\vinged Teal. 



I. 



Head shining green. 



Center of crown white or whitish. 



a. Side of head and neck reddish brown. 



b. Side of head and neck light, mottled. 

 Crown greenish, throat white. 



Crown dark olive brown. 

 Crown finely streaked with black. 



a. Wing coverts with chestnut. 



b. Wing coverts without chestnut. 

 (i). Sides barred with black. 

 (2). Sides plain brown. 



(3). Sides spotted with black. 

 Belly conspicuously marked or chestnut. 

 Underparts chestnut. 

 Underparts not chestnut. 



a. Lesser wing coverts bluish. 



b. Lesser wing coverts brownish gray, 

 (i). Speculum purple. 



(2). Speculum gray and white. 



312. Cinnamon Teal. 



311. Blue=\vinged Teal. 



312. Cinnamon Teal. 

 311. Blue=W'inged Teal. 



307. Mallard. 



B. C. & H. 23. European Widgeon. 

 309. American Widgeon. 

 315. Wood Duck. 

 314. Pintail. 



308. Gadwall. 



314. Pintail. 



309. American Widgeon. 

 308. Gadwall. 



313. Shoveller. 

 313. Shoveller. 



307. Mallard. 



308. Gadwall. 



