BIRDS OF NOETH AND MIDDLE AMERICA. 451 



Anisorainphe'^ Dumont, Diet. Sci. Xat., iv, 1805, 173, (Alternative substitute 

 name for Rynchops?) 

 (Generic characters same as Family characters.) 



KEY TO THE SPECIES AND SUBSPECIES OF RYNCHOPS. 



a. Under wing-coverts and axillars white or very pale brownish gray, in abrupt and 



conspicuous contrast with black along edge of wing; secondaries very broadly 



tipped with white; under tail-coverts white; lateral rec trices white or mostly so. 



(Rynchops nigra.) 



b. Axillars and under wing-coverts pure white; smaller (mng 350-401 in male, 



338-358 in female; culmen 63-72 in male, 52-57 in female). (Atlantic and 



Gulf coasts of United States, south in winter to Yucatan, Trinidad, etc.) 



Rynchops nigra nigra (p. 451).. 



bb. Axillars and under wing-coverts pale l>rownish gray or tinged with that color, 



larger (wing 385-412 in male, 382 in female; culmen 74.5-83 in male, 66 in 



female). (Atlantic coast of South America and Pacific coast of Central 



America and Mexico.) Rynchops nigra intercedens (p. 453). 



aa. Under wing-coverts and axillars brownish gray, not strongly contrasted with 

 blackish along edge of wing; secondaries very narrowly ti})ped with white ; under 

 tail-coverts brownish gray margined with white; lateral (as well as middle) 

 rectrices deep brownish gray narrowly edged with white. (Atlantic and Pacific; 

 coasts of South America; casual in Yucatan.). . Rynchops cinerascens (p. 455), 



RYNCHOPS NIGRA NIGRA (Linnaeus). 



BLACK SKIMMER. 



Adults in svm.riier (sexes aUke). — Forehead, lores, suborbital and 

 malar regions, and entire under parts (including axillars and under 

 wing-coverts), lateral upper tail-coverts, and broad tips to second- 

 aries and proximal primaries, immacubttc pure white; rest of plumage 

 (except tail), including auricular region, uniform black or sooty black; 

 tail mostly white, the middle pair of retrices grayish brow^n edged 

 with white, the remaining retrices more or less tinged at tips with 

 the same; basal half (approximately) of bill bright vermilion red (in 

 life), the mandible more scarlet, passing into orange or 3'ellow on 

 tomium, the terminal half black; iris dark brown; legs and feet rich 

 orange-vermilion (in life). 



Adults in winder.— Similar to summer adults but the black duller 

 and more brownish and interrupted by a broad collar of white across 

 lower hindneck. 



Young. — Upper parts light buff, each feather with a central spot 

 of blackish, these spots largest on scapulare; lores and suborbital 

 region uniform pale buff, the former, however, with a dusky space 

 immediately in front of eye; greater wing-cOverts blackish gray or 

 grayish black, tipped with white; secondaries white for most of their 

 exposed portion; primaries blackish, the fourth, fifth, and sixth (from 

 outside) margined terminally Avith light buff, the four inner (proxknal) 



""A^/iaos, unequal; pd^toos, beak. (Richmond.) 



