496 NORTH AMERICAN BIRDS. 



Adult male : Above dark dull blue, the back sometimes indis- 

 tinctly spotted with black; sides of head, chin, throat, 

 chest, sides of breast, and sides, uniform deep black ; rest 

 of lower parts white. (In winter, upper parts tinged with 

 olive-green, the chin and throat varied, more or less, with 

 white, and white of flanks tinged with brownish.) Adult 

 female : Above plain dull olive or grayish green, sometimes 

 tinged with blue; lower parts (including the portions 

 which are black in the male) plain pale greenish buff. 

 Young : Above dull brown, the wings (except coverts) and 

 tail as in adults ; a dull yellowish white superciliary stripe ; 

 below this, sides of head blackish in male, dull grayish 

 brown in female; lower parts yellowish white, more 

 brownish anteriorly. Length 4.70-5.50, wing 2.50-2.65, 

 tail 2.05-2.25. Nest on trees in high woods, 20-50 feet or 

 more from ground, compact, composed of fine dry grasses, 

 spiders' webs, lichens, strips of fine bark, etc., the cavity 

 1.40 deep by 2.00 across. Eggs usually 4, .68 X -49, buffy 

 whitish or greenish white, more or less heavily spotted 

 or blotched with reddish brown. Hab. Eastern North 

 America, breeding from northern New England and New 

 York northward, and southward along higher Alleghanies ; 

 in winter, Florida, Bahamas, and Greater Antilles. 



654. D. caerulescens (&MEL.). 



Black-throated Blue Warbler. 



d 1 . Outer surface of wings with more or less distinct lighter markings, 



but without white spot at base of quills. 

 e l . Eump yellow. 



fl . Crown with a yellow patch (partly concealed). 



g 1 . Adult male : Lower parts, including chin and throat, 

 white, the chest and sides broadly streaked with 

 black (these streaks sometimes more or less con- 

 fluent, forming a broken patch), and the sides 

 of the breast with a yellow patch; upper parts 

 bluish gray, becoming blackish on sides of head, 

 which are marked by white supraloral and post- 

 ocular streaks ; back broadly streaked with black ; 

 wing with two white bands across tips of middle 

 and greater coverts. Adult female: Similar to 

 male, but much duller in color, with markings 

 less conspicuously contrasted. Winter plumage 

 (sexes essentially alike") : Upper parts strongly 

 washed with umber-brown, and lower parts more 

 or less suffused with a paler wash of the same 

 the pattern of the summer plumage being thereby 



