BIRDS OF NORTH AND MIDDLE AMERICA. 455 



Rhynchops nigra (not Linnaeus) Maximilian, Beitr. Naturg. Bras., iv, 1833, 877 

 (Espirito Santo, s. Brazil).— Darwin, Zool. Voy. 'Beagle,' iii, 1839, IGl 

 (coast Uruguay) ; ed. 1841, iii, 143, part (hal)its). — ^Hartlaub, Index Azara's 

 Apunt., 1847, 26 (Paraguay).— Burmeister. Syst. Ueb. Th. Bras., iii, 1856, 

 454; Journ. fiir Orn., 1860, 267 (Rio Parana, Argentina); Reis. La Plata, ii, 

 1861 , 250 (Rio Parana).— Salvin, Ibis, 1865, 193 (Acapam, Guatemala); 1866, 

 200 (Acapam, Guatemala).— Pelzeln, Orn. Bras., 1870, 324, 461, part.— 

 ScLATER and Salvin, Proc. Zool. Soc. Lond., 1871, 566, part (monogr.). — 

 Lawrence Mem. Bost. Soc. N. H., ii, 1874, 318 (San Bias, Tepic; Rio Zaca- 

 tula, ColimaV — Berlepscii, Journ. fiir Orn., 1874, 279 (Santa Catarina, s. 

 Brazil; synonymy; crit.); 1887, 37 (Rio Pilcomayo, Paraguay), 126 (Para- 

 guay). — White, Proc. Zool. Soc. Lond., 1882, 628 (Buenos Aires). — Saunders, 

 Cat. Birds Brit. Mus., xxv, 1896, 153, part (Acapam, Guatemala, Jan.). — 

 Salvin and Godman, Biol. Centr.-Amer., Aves, iii, 1903, 416, part (San Bias, 

 Tepic; Rio Zacatula, Colima; San Mateo, Oaxaca?; Acapam, Guatemala). 



Rynchops nigra Durnford, Ibis, 1877, 200 (Buenos Aires). 



Rhynchops melanura (not of Swainson) Sclater and Hudson, Argentine Orn., ii, 

 1889, 193. 



Rhynchops intercedens Saunders, Bull. Brit. Orn. Club, no. 25, March, 1888, 

 p. xxvi (Sao Paulo, s. e. Brazil; coll. Brit. Mus.); Cat. Birds Brit. Mus., 

 xxv, 1896, 155 (Sao Paulo and Santa Catarina, s. e. Brazil; Buenos Aires, 

 Argentina). — Kerr, Ibis, 1901, 236 (Gran Chaco, Paraguay). — Hartert, 

 and Venturi, Novit. Zool., xvi, 1909, 254 (Avellaneda, etc., Argentina, 

 Dec; crit.). 



Rynchops intercedens Hellmayr, Novit. Zool., xv, 1908, 102 (Rio Araguaya, 

 Brazil; crit.). 



[Rhynchops] intercedens Sharpe, Hand-list, i, 1899, 138. — Forbes and Robinson, 

 Bull. Liverp. Mus., ii, no. 2, 1899, 56. 



Rhynchops nigra intercedens Ihering, RevistaMus. Paulista, iii, 1899, 442 (Iguape, 

 Sao Paulo, s. Brazil); iv, 1900. 106 (Sao Paulo); vi, 1904, 344 (Paraguay).— 

 Bertoni, Fauna Parag., 1913, 38. 



Rynchops nigra subsp. intercedens Dabbene, Orn. Argentina, July 16, 1910, 212. 



RYNCHOPS CINERASCENS Spix. 



DTTSKY-TAILED SKIMMER. 



Similar to R. nigra intercedens, but adults with under wing-coverts 

 wholly dee{> sooty gray, axillars light gray, secondaries very narrowly 

 tipped with white, and tail deep sooty, the rectrices (except middle 

 pair) very narrowly edged with whitish. 



Adults in summer (sexes alike). — Forehead, entire loral, suborbital 

 and malar regions and under parts immaculate white, shading into 

 brownish gray or under tail-coverts which, however, are whitish on 

 margins; axillars and proximal under wing-coverts light browiiish 

 gray, the rcmauiing under wing-.coverts much deeper brownish gray, 

 becommg blackish along edge of wing, the inner webs of remiges 

 deep brownish gray ]^assing into dusky terminally; crown (including 

 posterior portion of forehead), occiput, nape, hindneck, auricular and 

 orbital regions (narrowly in front of and beneath eyes) and upper 

 parts generally plain black or sooty black, the secojidaries narrowly 

 and not abruptly tipped with white, the lateral upper tail-coverts with 



