164 



BIRDS OF ILLINOIS. 



wings, more even tail, and larger toes and claws. It is also very 

 similar to Siiiiriis, differing chiefly in the longer wings, larger claws, 

 and absence of spots beneath." (Hist. N. Am. B.) 



Common Charactebs. Above plain olive-green, beneath plaiu yellow (except on throat 

 ami juculum, in 0. agilis alone). 



1. 0. agilis. Adult male: Head, neck and jugulum ash-gray, lighter on the throat and 

 tinged with olive on the crown; a distinct white orbital ring. Adult female: Throat 

 and jugulum light smoky gray, upper head and nape olive, like the back, and yellow' 

 of lower parts paler and duller. Young in first autumn: Similar to the female, but 

 throat and jugulum still duller and more or less tinged with dull yello^vish. 



2. 0. formosa. Adult male: Crown bUck, the feathers tipped with ash-gray: lores and 

 triangular patch on aurieulars black; broad superciliary stripe, spot on lower eyelid, 

 and entire lower parts rich yellow. Adult female: Similar to the male, but rather 

 duller. Young: Like the adult female, but still duller, the black patches concealed 

 or replaced by dusky smoky olive. 



Geothlypis agilis (Wils.) 



CONNECTICUT WAKBLEE. 

 Popular synonym. Gray-headed Warbler. 



l<uh-ia agilis Wils. Am. Orn. v. 18ia, 64, pi. 39, fig. 4.— AuD. Orn. Biog. II. 1S34, 227, pi. 138. 

 Trifhas agilis Nutt. Man. 2d ed. i, 1840, 4C3, 



Hylvicola agilis Jakd.— AuD. Synop. 1S39, 63; B. Am. ii, 1841. 71. pi. 99. 

 Oporornis agilis Baikd, B. N. Am. 1S58, 246; ed. 18C0. pi. 79. flg. 2; Cat. N. Am. B, 18S9. 

 No. 174; Review, 1S65, 218.— CouES, Key, 1872,106; Check List, 1873, No. 95; 2d ed. 1882. 

 No. 139; B. Col. Val. 1878. 308. -B. B. & R. Hist. N. Am. B. i. 1874. 290, pL 15, flgs, 1, 2.— 

 RiDGW, Nom. N. Am. B. 1881, No. 118. 

 Trichas tephrocotis Nutt. Man. 2d ed. i. 1840, 462. 

 Hab. Eastern United States and British Provinces, migrating northward in spring 

 chiefly through the Mississippi Valley, and returning southward in autumn through the 

 Atlantic Suites. Winter residence unknown, but probably in Gulf States, there being no 

 extrallmital record. Breeds in Manitoba, and probably elsewhere in the interior of 

 British America. 



"Sp. Chae. Spring male. Upper parts and sides of the body uniform olive-green, very 

 slightly tinged with ash on the crown. Sides of the head ash, tinged with dusky beneath 

 the eye. (Entire head sometimes ash.) Chin and throat grayish ash, gradually becoming 

 darker to the upper part of the breast, where it becomes tinged with dark ash. bides of 

 the neck, breast, and body, oUve, Uke the back ; rest of under parts Ught yellow. A broad 

 continuous white ring round the eye. Wings and tail feathers olive (especially the latter), 

 without any trace of bars or spots. Bill brown above. Feet yellow. Length, 6 inches; 

 wing, 3.00; tail, 2.25. Female. The olive green reaching to the bill, and covering sides 

 of head; throat and jugulum pale ashy buff. You)ig not seen. NestUng unknown. 



"Autumnal specimens nearly uniform olive above ; the throat 

 tinged with brownish so as to obscure the ash. 



"A specimen in the collection of the Philadelpliia Academy, killed 

 by Mr. Krider, has the darker ash of the jugulum of a decided 

 sooty tinge. 



"A pecuharity in the history of this species is shown in the fact 

 that it is quite abundant in llhnois, Wisconsin, etc., in the spring. 



