356 BIRDS OF ILLINOIS. 



Although less numerous than the Acadian Flycatcher, at least in 

 the southern part of the State, Traill's Flycatcher is not an un- 

 common summer resident. In general habits it so much resembles 

 the species named as to be uiidistinguishable except by the critical 

 observer. The two are often found in the same localities, but Traill's 

 Flycatcher is of a more familiar disposition, and may often be found 

 in close proximity to dwellings, especially in orchards, while the 

 other is seldom seen in such places. 



Empidonax acadicus (Gmel.) 



ACADIAN FLYCATCHER. 



Popular synonym. Green- crested Flycatcher. 



Muscicapa acadica GMEL. S. N. i, 1788, 947. AUD. Orn. Biog. ii, 1834, 256; v, 1839. 429, 



pi. 144; Synop. 1839, 42; B. Am. i, 1840,221, pi. 62. 

 Empidonax acadicus BAIKD, B. N. Am. 1858, 197; Cat. N. Am. B. 1859, No. 143. COUES. 



Key, 1872, 174;List,1874,No. 256; 2d ed. 18S2, No. 384; B. N. W. 1874, 249. B. B. & E. 



Hist. N. Am. B. ii, 1874,374 pi. 44, fig. 11. RIDGW. Norn. N. Am. B. 1881, No. 324. 

 Muscicapa auerula "ViEiLL." WILS. Am. Orn. ii, 1810, 77, pi. 13, fig. 3 (nee YIEILL.). 



HAS. Eastern United States, breeding nearly throughout, but rare in New England, 

 where scarcely found beyond the Connecticut valley; north, in the interior, to Canada 

 West. In winter, Cuba and Yucatan, possibly Gulf States also. 



"Sp. CHAK. The second and third quills are longest, and about equal; the fourth a 

 little shorter; the first about equal to the fifth, and about .35 less than the longest. Tail 

 even. The upper parts, with sides of the head and neck, olive-green; the crown very 

 little if any darker. A yellowish white ring round the eye. The sides of the body under 

 the wings like the back, but fainter olive; a tinge of the same across the breast; the 

 chin, throat, and middle of the belly white; the abdomen, lower tail and wing-coverts, 

 and sides of the body not covered by the wings, pale greenish yellow. Edges of the 

 first primary, secondaries and tertials margined with dull yellowish white, most broadly 

 on the latter. Two transverse bands of pale yellowish (sometimes with an ochrey 

 tinge) across the wings, formed by the tips of the secondary and middle coverts, suc- 

 ceeded by a brown one. Tail light brown, margined externally like the back. Upper 

 mandible light brown above; pale yellow beneath. In autumn the lower parts are more 

 yellow. Length. 5.65; wings, 3.00; tail, 2.75. Young (60892, Mt. Carmel, 111., August 11, 

 1870; R. RIDGWAY): Whole upper surface with indistinct transverse bars of pale och- 

 raceous; wing-markings light ochraceous. 



This species is very similar to E. traillii, but the upper parts 

 are of a brighter and more uniform olive-green, much like that of 

 Vireo olivaccus. The feathers of the crown lack the darker centre. 

 There is less of the olivaceous ash across the breast. The bands 

 across the wing are light yellowish, instead of grayish olive. There 

 is much more yellow at the base of the lesser quills. The wings 

 are longer, both proportionally and absolutely. The primaries ex- 



