TYRA2v^NID^ — THE FLYCATCHERS. 353 



Contopus borealis, P.aird. 



OLIVE-SIDED FLYCATCHER. 



Tyrannus borealis, S\v. &, Kicu. F. Bor.-Am. II, 1831, 141, plate. Myiobius borealis. 

 Gray, Genera, I, 248. Musdcapa euoperi, Nuttall, Man. I, 1832, 282. — AuD. 

 Orn. Biog. II, 1834, 422 ; V, 1839, 422, pi. clxxiv. — Ib. Synopsis, 1839, 41. — Ib. 

 Birds Am. I, 1840, 212, pi. Iviii. Tyrannus coopcri, Bo.nap. List, 1838. — Nuttall, 

 Man. I, (2J. ed.,) 1840, 298. Contopus cooperi, Cab.\nis, Journal fur Ornitliol. Ill, 

 Nov. 1855, 479. ilitscimpa inomata, Nuttall, Man. I, 1832, 282. Contopus borealis, 

 Baird, Birds N. Am. 1858, 188. — Cooper & Suckley, 169. — Sclater, Catal. 1862, 

 230. — Samuels, 135. — Cooper, Orn. Cal. I, 1870, 323. Contopus mesoleucus. Scla- 

 ter, P. Z. S. 1859, 43. — Ib. Ibis, 1859, 122, 151. Tyrannus nigricans, Max. Cab. 

 J. VI, 18.58, 184. 



Sp. Char. Wings long, much pointed ; the second quill longest ; the first longer than 

 the third. Tail deeply forked. Tarsi short. The upper parts ashy-brown, showing 

 darker brown centres of the feathers ; this is emi- 

 nently the case on the top of the head ; the sides of 

 the head and neck, of the breast and body, resem- 

 bling the back, but with the edges of the feathers 

 tinged with gray, leaving a darker central streak. 

 The chin, throat, narrow line down the middle of the 

 breast and body, abdomen, and lower tail-coverts 

 white, or sometimes with a faint tinge of yellow. 

 The lower tail-coverts somewhat streaked with Ijrown 

 in the centre. On each side of the rump, generall}' 

 concealed by the wings, is an elongated bunch of 

 white silky feathers. The wings and tail very dark 

 brown, the former with the edges of the secondaries 

 and tertials edged with dull white. The lower wing- 

 coverts and axillaries grayish-brown. The tips of the Contopus borraiix. 

 primaries and tail-feathers rather paler. Feet and 



upper mandible black, lower mandible brown. The young of the year similar, but the 

 color duller ; edges of wing-feathers dull rusty instead of grayish-white. The feet light 

 brown. Length, 7.50 ; wing. 4.33 ; tail, 3.30 ; tarsus, .60. 



Hab. Northern portions of whole of North America, throughout Rocky Mountains, 

 south through elevated regions of Mexico to Costa Rica. Localities : Oaxaca, high regions, 

 Oct. (ScL. 1858, 301) ; Xalapa (Scl. 1859, 366) ; Guatemala (Scl. Ibis, I, 122) ; Costa 

 Rica (Lawr. IX, 115); Veragua (Salv. 1870, 199) ; San Antonio, Texas (Dresser, Ibis, 

 1865, 474, winter). 



There is wonderfully little variation in thi.s specie.s, both in coloration and 

 size, with different regions ; in fact none other than individual can be 

 observed. Contrary to the usual rule, spring specimens have a more 

 appreciable sulphur-yellow tinge below. 



Habits. This still comparatively rare species was first obtained by Itich- 

 ardson and described by Swain.son. The specimen was shot on the Sas- 

 katchewan. No other was taken, and no information was obtained in reference 

 to its habits. It appears to have been next met with by Mr. John Bethune, 

 in Cambridge, June 7, 1830, in the woods of Mount Auburn. This and a 



VOL. IL 45 



