186 TRA ILL' S FL YCA TCHER. 



EMPIDONAX TEAILLI. 



Traill's Flycatcher. 

 Empidonax Trailli BAIRD, Birds N. A.; 1858, 193. 



DESCRIPTION. 



SP. Cn. Form, slender. Size, medium. Sternum, not stout. Tongue, thin and flat but not horny, provided with a 

 bifid tuft of cilia at tip which extend along the side for one third of the terminal length; yellow in color. Stomach, quite 

 muscular. Larynx, provided with a thick and strong sterno-trachealis. Broncho-trachealLs quite well developed, also bron- 

 chial is. 



COLOR. Adult. Above, including upper tail coverts, uniform olivaceous-green, with the foathers of the head showing 

 dusky centers. Wings and tail, dark-brown, with the outer feathers of the latter, lighter. Tips, edges of the terminal two 

 thirds of the secondaries, outer edges of the tertiaries, tips of primaries and of two rows of wing coverts, forming bars, yel- 

 lowish-white. Beneath, yellowish-white, becoming darker on the abdomen and under tail coverts. Sides, flanks, and band 

 across breast, olivaceous. Under wing coverts, yellowish. There is a narrow, yellowish ring around the eye but the lores 

 are olivaceous mixed with dusky. Bill, brown, yellow on lower mandible. Feet, brown. 



Nnsllinys. Above, very olivaceous-brown. Beneath, yellowish. The band on the breast is scarcely discernible and 

 the other dark markings below are not nearly as extended. Sexes, similar in all stages . 



OBSERVATIONS. 



Specimens vary greatly, being often as light as typical Least Flycatchers, from which it is difficult to distinguish them. 

 In lifj, the two species are so different that any one can decide between them, but with the dried skins this Is not as easy. 

 Although the experienced ornithologist separates them rather by intuition than by actual differences, yet I find by careful 

 study of a large series of both spscies that the following characters in Traill's Flycatcher are more or less constant. The 

 size is generally larger but not always. The bill h usually broader but this cannot be depended upon; while the yellow 

 under mandible, which in life is veined with purple, is not a point that counts for much as the Least Flycatcher occasion- 

 ally shows one that is similar. Now for tire true differences. The plumage of Trai/ti is very silky, the rump is as dark as 

 as the back, the circle around the eye is quite narrow and yellow, while the lores nre decidedly olivaceous. The differen- 

 ces between this species and other members of the genus are given under observations in the succeeding pages. Distrib- 

 uted in summer throughout New England north of latitude 43 J , and across the continent; ranging as far south in the west, 

 however, as latitude 37 J and north into the Fur Countries; the western form (pusil/us ) now being considered identical 

 with the eastern. Winters in Mexico and Central America. 



DIMENSIONS. 



Average measurements of eleven specimens from New England. Length, 5 'fiO; stretch, 8'25; wing, 2-6 r >; tail, 2'58; 

 bill, '66; tarsus, '45. Longest specimen, 5'75; greatest extent of wing, 8'75; longest wing, 3'75; tail, 2'70; bill, '70; tarsus, 

 60. Shortest specimen, 5'29; smallest extant of wing, 7'75; shortest wing, '2'50; tail, 2'28; bill, "6!); tarsus, '40. 



DESCRIPTION OF NESTS AND EGOS. 



Nests, placed in trees, composed of sticks and weeds lined with dried grass. Dimensions, external diameter, 3'00, inter- 

 nal, 1-75. External depth, 1'50, internal, 1-00. 



Eyys, three to four in number, oval in form, creamy-white in color, spotted and blotched irregularly with reddish- 

 brown. Dimensions from '75 x '50 to '78 x '55. 



HABITS. 



For several of the earlier years of my ornithological experience, I looked in vain for 

 Traill's Flycatcher and the region about my home underwent a careful scrutiny. Many 

 an innocent Least Flycatcher fell when he chanced to wander into the woods where I was 

 looking for its rarer relative. All this close study into the habits of at least one species of 

 the genus greatly aided me in after years and, when on the first of June, 18G9, 1 did meet 

 with the first specimen of Traill's Flycatcher that I had ever seen living, I recognized it, 

 even before shooting, as being something new. It is not at all strange that I missed find- 

 ing this little bird so long, as now, with all my experience with the species, I should be 

 obliged to let many migrating seasons pass without finding one in Eastern Massachusetts. 



