POLIOPTILA. 569 



branch, deeply cup-shaped, very compact, composed of plant-fibres and other 

 felted materials, lined with soft feathers, and often beautifully decorated exte- 

 riorly with variously colored lichens. Eggs 3-5, greenish or bluish white, speckled 

 with brown. 



a 1 . Exposed portion of outer tail-feather entirely white. 



b 1 . Top of head in adult males plumbeous-blue, bordered anteriorly and later- 

 ally by a black line ; in female, bluish ash-gray, not markedly different 

 from lighter gray of sides of head. 



c l . Lower parts white medially, pale ash-gray laterally ; upper parts clear 

 grayish blue or plumbeous, deeper on top of head, decidedly paler 

 on rump; length 4.05-5.50, wing 2.00-2.20 (2.07), tail 2.05-2.20 

 (2.15). Nest always (?) beautifully decorated with lichens. Eggs 

 .56 X -43. Hab. United States, chiefly south of 42, wintering in 

 Gulf States, western Cuba, Bahamas (occasionally), Mexico, and 



Guatemala 751. P. caerulea (LINN.). Blue-gray Gnatcatcher. 



c 2 . Lower parts light bluish gray, deeper laterally ; upper parts deep bluish 

 plumbeous, somewhat bluer on top of head, but scarcely, if at all, 

 paler on rump ; about the size of P. ccerulea. Hab. Bahamas 

 (Abaco and New Providence ; resident) ; Cozumel ? 



P. caerulea csesiogaster KIDGW. Bahaman Gnatcatcher. 1 



b*. Top of head in adult males glossy black ; in females and young dark bluish 

 gray or plumbeous, abruptly contrasted with whitish of sides of head 

 (the latter sometimes including a distinct superciliary streak). 

 c l . Tertials broadly and conspicuously edged with pure white. 



d l . Lores partly (sometimes entirely) white ; occiput (in adult male), 

 as well as crown and forehead, glossy black; length about 

 4.00-4.25, wing 1.90-2.00, tail 1.90-2.10. Hob. Southern Mex- 

 ico (Tehuantepec, etc.), Guatemala, Salvador, and Nicaragua. 



P. albiloris SCL. & SALT. White -lored Gnatcatcher. 2 

 d 2 . Lores entirely black in adult males, dull grayish in females and 



young. 



e l . Otherwise like P. albiloris ; length about 4.25-4.50, wing 1.85- 



2.10, tail 2.00-2.20. Hab. Brazil (Bahia, etc.) to Nicaragua. 



P. leucogastra (MAX.). Maximilian's Gnatcatcher. 3 



e 2 . Smaller, and with occiput light bluish gray, like hind-neck, 



back, etc. ; length 3.75, wing 1.85, tail 1.75. Hab. Yucatan. 



P. albiventris LAWR. Lawrence's Gnatcatcher.* 



c 2 . Tertials inconspicuously edged with dull grayish white or light grayish. 



d 1 . Lores, superciliary region, and upper half of ear-coverts glossy 



black in adult male, ash-gray in female and young; length 



1 New subspecies ; seventeen specimens examined. 



2 Polioptila albiloris SCL. & SALV., P. Z. S. 1860, 298. 



3 Sylvia leucogastra MAX., Beitr. iii. 1831, 710. Polioptila leucogastra Set,., Cat. Am. B. 1862, 12. 



4 Polioptila albiventris LAWR., Ann. N. Y. Ac. Sci. iii. No. 9, 1885, 273. 



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