726 BULLETIlSr 50, UNITED STATES NATIONAL MUSEUM. 



POLIOPTILA BAIRDI Ridgway. 

 NICARAGTIAN GNATCATCHER. 



Similar to P. alhiloris^ but wing and tail shorter, especially the 

 latter; adult male with loral region parti}' l)lack, usually as a spot at 

 anterior angle of eye or a streak from anterior angle of eye to, or 

 nearly to, base of maxilla. 



Adult male. — Length (skins), 1U5-108 (106); wing, 46-50 (47.5); 

 tail, 45^9 (46.8); exposed culmen, 11. .5-12.5 (11.9); tarsus, 17-18 

 (17.5); middle toe, 9-9.5 (9.2).« 



Adult female. — Length (skins), 106; wing, 43.5-46.5 (45); tail, 42.5- 

 44 (43.5); exposed culmen, 12; tarsus, 17-17.5 (17.3); middle toe, 

 9-9.5 (9.3).* 



Western Nicaragua (Kealejo; San Juan del Sur; Sucuya; Grenada) 

 and Costa Rica (Liberia; Volcan de Miravalles; Cartago?) 



Polioptila albiloris (not of Sclater and Salvin) Baird, Review Am. Birds, 1864, 

 70, part (description; Grenada and Realejo, Nicaragua). — Salvin and God- 

 man, Biol. Centr.-Am., Aves, i, 1879, 53, part (Grenada and Realejo, Nica- 

 ragua). — Nutting, Proc. U. S. Nat. Mus., vi, 1883, 373 (San Juan del Sur, 

 Nicaragua). — Zeledon, Anal. Mus. Nac. Costa Rica, i, 1887, 105 (Liberia and 

 Cartago, Costa Rica). 



P{_olioptUa] albiloris Ridgway, Proc. U. S. Nat. Mus., v, 1882, 387, 388, 389, part 

 (Realejo, Nicaragua); Man. N. Am. Birds, 1887, 569, part (Nicaragua). — 

 (?) Hellmayr, Novit. Zool., vii, 1900, 536, in text, part (crit. ); Tierreich, 

 18 Lief., 1903, 28, part (Nicaragua; Miravalles, Costa Rica). 



Polioptila bilineata (not Cnlicivora bilineata Bonaparte) Nutting, Proc. U. S. Nat. 

 Mus., vi, 1883, 380, part (Sucuyd, Nicaragua). 



P\_olioptila'] leucogastra {not Sylvia leucogastra Maximilian) Ridgway, Proc. U. S. 

 Nat. Mus., V, 1882, 387, in text, 388, part (Grenada, Nicaragua). 



J'loliopiilal albilora Ridgway, Proc. U. S. Nat. Mus., v, 1882, 388, in text, part 

 (Realejo, Nicaragua). 



Polioptila bairdi Ridgway, Proc. Biol. Soc. Wash., xvi, Sept. 30, 1903, 110 (San 

 Juan del Sur, Nicaragua; coll. V. S. Nat. Mus.). 



POLIOPTILA BILINEATA (Bonaparte). 

 BONAPARTE'S GNATCATCHER. 



Similar to P. hairdi, but with loral region entirely white, confluent 

 with a broad superciliary streak (as in P. superciliaris)\ wing averag- 

 ing longer, tail decidedly shorter, and feet smaller.'' Similar in head- 

 pattern to P. superciliaris^ but bird decidedly larger and coloration 

 much paler, the gray of back, etc., and white of under parts being as 

 in P. alljiloris and P. l>alrdl. 



Adidt male.— Length (skins), 100; wing, 48-50 (49); tail, 42-44 (43); 

 exposed culmen, 11.5-12 (11.8); tarsus, 15-16.5 (15.8); middle toe, 8-9 

 (8.3).* 



« Six specimens. 

 ^ Three specimens. 



c These differences of proportions are very obvious in adult males (especially as to 

 the both relatively and absolutely shorter tail), less so in females. 



