TYIIANNID^— THE FLYCATCHERS. 333 



decidedly darker (except in var. Idivreiicei) ; throat and Jufjuliim ashy-white ; 

 rest of lower parts sulpliur-yuUow. Ilab. Central and South Aiueriuii, and 

 Jamaica. 



Pileuni sooty-brown, decidedly darker than the back ; wings and tail 

 entirely (lestitutc of nilbiis edgin},'s, except a faint tinge on outer webs 

 of inner secondaries and rectrices, towards the biuse. Tail faintly 

 rounded. Wing, 3.00; tail, 3.10; cuhnen, .80: tarsus, .65. Ilab. 

 Jamaica var. tristis.^ 



Pileum grayish-brown, not appreciably darker than the back ; outer 

 webs of inner secondaries and primaries and rectrices faintly edged 

 with rufous. Wing, 2.80-3.40; tail, 2.85-3.45; cuhnen, .85 -.90; 

 tarsus, .75 -.80. Hab. Northern Mexico, from northern boundary, 

 south to Colima, Tchuantepec, Yucatan, and Salvador . var. lawrencei? 



Pileum sooty-blackish, decidedly and abruptly darker than the back. 

 Outer weljs of wing-coverts, primaries, secondaries, and rectrices dis- 

 tinctly edg(Ml with rufous. Yellow beneath brighter than in lawrencei. 

 Wing, 3.20-3.30; tail, 3.15 -3.30; cuhnen, .80 -.85; tarsus, .75 -.80. 

 Hab. Central America from Panama to Guatemala (grading into var. 

 i«iiTe«cet in Tehuantepec, and Orizaba) . . . var. nigricapillus.' 



Pileum ileep black, abruptly difTcrent from the greenish-olive of the 

 b.ick, and separated fi-om it by a more ashy shade. Wings and tail 

 wholly destitute of rufous edgings. Yellow beneath brighter than in 

 var. nigrimpiUns. Wing, 3.20 ; tail, 3.20 ; culmen, .85 ; tarsus, .78. 

 Tail about even. Hab. Northwest South America, from Ecuador 

 northward (grading into nigricapillus on Isthmus of Panama). 



var. nigriceps.* 



* Mijiarchm tristii (Gosse), CouES. Mgiobius trislis, Gosse, B. Jam. 167, pi. xli. Myiarclvist. 

 CouEs, 1'. A. N. S. .luly, 1872, 80. 



' Mfliarchiis tristis, var. hncreitcci {(\i\i\vd), Baird. Tyrannula lau-rcncei, GiH.\un, 10 sp. 

 Tex. B. pi. ii. Myiarchm I. Baikd, Birds N. Am. 1858, 181, pi. xlvii, f. 3. — Coues, P. A. N. S. 

 July, 1872, 74. 



Obs. — The most typical specimens are from Mazntlan and northward, across the northern 

 portion of Mcxiio. On the eastern coast, specimeiis from Mi.'|Wlor and Or'Izaba alKjady strongly 

 incline townnl var. niijricapilhis. * 



' .\[iji(in-hm tristi.i, var. iii(/riaipilfi(.i, C'aban'IS. " Myiarchii.i ninricapillHn, Cahan." Sci,. 

 t'at. Am. 15. 1802, 2y3, et Auct. M. lairrnicci, C'oi;ks, V. A. X. S. 1872, 74 (in i)art). 



Obs. — A very strongly diU'erentiated form, hut unciucstioiiably grading into var. laiorcncei on 

 the one hand, and var. »/;/c(Vry« on tlie otlier. 



* Mjliiirchm trixti.i, var. nigriir/is, Sci.Ariai. .Uijiarchus nigrkrps, ScL. P. Z. S. 1860, 08, 

 295. — ('(.fi;s, P. A. X. S., July, 1872, 75. 



Obs. — The last tln'ee races appear to be all n'dueihle to one .s|>ecies, as, taking the large series 

 of spceimens before us (over .30 skins), we fuiil it impossible to draw the line between them. 

 Specimens from Southern Mexico are referrible, with eipial |)ropriety, to hnrivturi or to niijriea- 

 pillus, while .skins from I'anaina of nl<jrici'im are less typical than those from Ecuador. This 

 case of gradually increasing niclaiiistic tendency as we proceed southward alfords an exact parallel 

 to that of Vircosijlvm yihus and K. jumplice, Hai/oniis nigricans and H. aqua/icus, anil many 

 other cases. 



