BIRDS OF NOETH AND MIDDLE AMERICA. .315 



Largo Tringinse (wing 175-220 mm.) with the very stout bill 

 nearly as long as tarsus; a distinct web between basal portion of 

 inner and middle (as well as between outer and middle) toes, and with 

 basal portion of primaries extensively white. 



Bill nearly as long as tarsus, stout, but compressed, its depth at 

 base equal to about one-sixth the length of exposed culmen; nasal 

 groove broad, extending about half way to tip of maxilla; nostril 

 considerably anterior to loral antia, narrowly elliptical, longitudinal. 

 Wing ample, pointed, the longest primary (outermost) exceeding 

 distal secondaries by less than half the length of wing. Tail 

 more than one-third as long as wing, truncate or very slightly 

 rounded; rectricesl2. Tarsus decidedlymorethan one and a half times 

 as long as middle toe without claw, continuously scutellate both 

 anteriorly and posteriorly; bare portion of tibia about half as long 

 as tarsus, scutellate behind and for upper portion in front; outer toe 

 slightly but distinctly shorter than middle toe, slightly longer than 

 inner toe; basal phalanges of outer and middle toes united by a web, 

 the inner and middle toes united at base by a slightly smaller web. 



Coloration. — Under parts and upper tail-coverts mostly white, the 

 primaries extensively white basally, blackish or dusky distally; rest 

 of plumage brownish gray, in summer streaked and barred or spot- 

 ted, more or less with blackish. 



Range. — North America (South America in migration.) (Mono- 

 typic.) 



KEY TO THE SUBSPECIES OF CATOPTROPHORUS SEMIPALMATUS. 



0. Smaller, with relatively shorter and thicker bill (wing, 175-195.5; tail, 66.5-74; 

 exposed culmen, 52.5-59; tarsus. 51.5-58; middle toe, 31.5-36); sTimmer adults 

 with upper parts darker, more olive-grajish, more heaAdly spotted or barred 

 with dusky, and with anterior and lateral under parts more heavily marked 

 with dusky. (Eastern United States; Bahamas; etc.). 



Catoptrophorus semipalmatus semipalmatus (p. 315). 

 aa. Ivarger, with relatively longer and more slender bill (wing, 193-220; tail, 73-88; 

 exposed culmen, 56-65; tarsus, 57-70; middle toe, 32.5-39); summer adults 

 with upper parts paler, more ashy gray, less hea\-ily marked with dusky, the 

 anterior and lateral imder parts also less heavily marked. (Western United 

 States, British ('ohmibia, Alberta, etc., east to Mississippi Valley; occasional 

 during migration along Atlantic and Gulf coasts.) 



Catoptrophorus semipalmatus inornatus (p. 319). 



CATOPTROPHORUS SEMIPALMATUS SEMIPALMATUS (Gmelin). 



WILLET. 



Adults in summer (sexes alike). — General color of upper parts 

 brownish gray, the pileum and hindneck streaked with dusky, the 

 back and scapulars irregularly spotted and barred with dusky or 

 blackish; wing-coverts nearly plain browiiish gray, becoming paler 

 on greater coverts; secondaries largely white; primaries white for 



