SYLVIID^ — THE SYLVIAS. 81 



Polioptila melanura, Lawr. 



BLACK-CAPPED GNATCATCHER. 



Culkivora atrica^nlla, LAWKENCBi Ann. N. Y. Lye. V, Sept. 1851, 124 (not of Swainson). 

 Culicivora mexicana, Cassin, lllust. I, 1854, 164, pi. xxvii (not of Bon.). FoUojHila 

 melanura, Lawrence, Ann. N. Y. Lye. VI, Dee. 1856, 168. — Baird, Birds N. Am. 

 1858, 382; Review, 68. — Heermann, P. R. R. R. vol. X (Williamson), 1859, 39.— 

 Cooper, Birds Cal. I, 37. 



Sp. Char. Above plumbeous-blue. Wliole crown, to bill and eyes, with tail, lustrous 

 blue-black. Beneath pale bluish-gray, almost white on chin and anal region ; the flanks 

 and crissum tinged with brown. Edge of eyelids, and margin and tip of outer web of 

 first and second lateral tail-feathers, white. Female and young without the black of the 

 crown. Length, 4.15 ; wing, 1.85 ; tail, 2.10. 



Hab. San Diego to Fort Yuma and Cape St. Lucas. Arizona, Coues. 



Specimens of this species from Cape St. Lucas differ from those of San 

 Diego described in the P. E. E. Eeport (7,191) in having the whole of the 

 outer web of the outer tail-feather white, and in a rather larger white tip. 

 The colors beneath are a little less ashy, though not of a pure white. Tlie 

 ash of the back is rather lighter and purer. The lores are ratlier lighter. 

 The first primary is a little larger and broader. 



It is possible tliat the restriction of the white of the outer web of the 

 exterior tail-feather to the outer half only is an unusual circumstance, as 

 both Mr. Cassin and Mr. Lawrence, in their descriptions, speak of the entire 

 outer web being white, — the second feather being of tlie former character. 

 LTnder these circumstances there will be little specific difference between 

 the tails of F. melanura and plumhca. The female birds will then be 

 separated by the light superciliary line and much shorter tarsi of F. 

 pln7nhea, — the latter measuring .63 instead of nearly .70 of an inch. 



Habits. This species was first noticed as belonging to the North 

 American fauna by Captain McCown, who obtained it near Einggold Bar- 

 racks in 1850. It has since been noticed at Fort Yuma and at San Diego, 

 and obtained in greater abundance at Cape St. Lucas. It is also found in 

 Mexico. Dr. Cooper says that it is common all winter both at San Diego 

 and at Fort Mohave. It has been traced as far north as latitude 30° in the 

 Sierra Nevada. Its song he describes as a harsh ditty of fi\e parts, some- 

 thing like a wren's song, with notes like those of a SAvallow, and also closely 

 resembling the song of Vireo belli. Their scolding note is a faint mew, like 

 that of a cat. 



The ]ial)its of this species appear to be not unlike those of the peculiar 

 family to which it belongs. All its members are among our smallest birds, 

 are almost exclusively inhabitants of woods, and resemble the Rcguli in 

 their restless activity in pursuit of the smallest insects on which they feed. 

 This bird is described as particularly active, quick in its movements, search- 

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