NATURAL SCIENCES OF PHILADELPHIA; 63 



Summer resident ; rare. Arrives early in April : remains until October. 

 Bill black above ; bright yellow below, except at its extreme tip. Mouth 

 yellow at all seasons. Iris brown. Subject to only very slight variations in 

 size. 



One of the most strongly marked of our Empidonaces. Its essential char- 

 acters lie in the much elongated and very narrow bill ; the long tarsi ; the 

 tail not forked, but rather the reverse ; and the conspicuously contrasted 

 white outer web of the exterior rectrices. Its colors are almost precisely 

 those of Hammondii, but the proportions of the two birds are quite different. 



There are several discrepancies between the present bird and the brief and 

 unsatisfactory description of Swainson above cited, as shown by Prof. Baird, 

 who proposes the name " Wrightii" in the event that the Mexican bird 

 proves distinct from that of the United States. 



[Note. Dr. J. Gr. Cooper furnishes me with the following: " Empidonax 

 Traillii. I have found this species west of the Mojave River and Cajou Pass, 

 and at Santa Barbara, in California. It was abundant at Fort Mojave : a shy 

 aud retiring species ; keeping in the willow and cotton wood copses of the 

 river bottom." Though disliking to suppose an error of identification in so 

 judicious a naturalist, I am of opinion that the note refers to pusillus, and not 

 to Traillii. Still Traillii is found in Mexico, and may very possibly ascend 

 the valley of the Colorado.] 



MITREPHORUS Scl. 



Mitrephorus, Sclater, P. Z. S., 1859, p. 44; type M. phwocercus Scl. 



A genus founded by Dr. Sclater, as above, to receive certain small Tyran- 

 nuline forms, closely allied to Empidonax, but differing from that genus in 

 the elongation of the occipital feathers, and a general fulvous or buffy suffu- 

 sion which tinges all the colors of the species. 



To the genus thus based upon M. plueocercus from Central Mexico, also 

 belongs the Musccapa fulvifrons of Giraud. A third species is one recently 

 described by Mr. Lawrence,* from Costa Rica, as M. aurantiiventris, differing 

 from phaiocercus in being rather smaller, the rusty fulvous of the under parts 

 much lighter, becoming bright orange yellow on the abdomen and sides, etc. 



I have the pleasure of introducing this neotropical genus into the United 

 States Ornis, upon specimens taken at Fort Whipple, of a species I shall 

 describe as new ; but which is so closely allied to M. fulvifrons that the two 

 may hereafter prove to be identical. 



69. Mitrephorus pallescens Coues, nov. sp. 



??Tyr<mnula afftnis, Swainson, f Syu. Mex. Birds, Phil. Mag. i. 1827, 



p. 366. 

 ? Muscicapa fulvifrons, Giraud, B. Texas, pi. 2, fig. 2, == Empidonax 

 fulvifons, Scl. P. Z. S., 1858, p. 301, = Mitrephorus fulvifrons, Scl. 

 P. Z. S., 1859, p. 45, = Empidonax rubicundus, Cab. Mus. Hein, ii. 

 p. 70. 

 Empidonax pygmccus Coues, Newton's Ibis, 1865. (MS. name men- 

 tioned in text.) 

 Sp. Ch. Above plain dull grayish brown, tinged with olive, particularly 

 on the middle of the back; the head and rump hardly appreciably thus 

 tinged. Below very pale fulvous, most pronounced across the breast, the 

 chin and throat being much lighter, and the abdomen almost white. No ful- 

 vous suffusion about the forehead ; the dark feathers of the crown reaching to 

 the bill ; the space between eye and bill, the auriculars and sides of the head 

 generally light brownish olive, with no trace of fulvous. Wings and tail plain 



* Annals Lye. Nat. Sci. Hist. New Y >ik, viii. Nov., 1865, p. 174. 



t '/'. utfinis aw. I.e. "Olive, beneath pale fulvous; wing coverts and quills with pale margins; 

 base of lesser quills with a blarkish spot; bill small; under mandible yellow; tail divaricate." 



I860.] 



