Jan., 191SJ Status of Empidonax TraiUii 95 



Seasonal variation does not seem to be quite so strongly- 

 marked as in Empidonax traillii traillii, though summer birds 

 are more brownish (less olivaceous) or more grayish, and paler 

 than in autumn, spring or winter. 



Birds in juvenal plumage, compared with the same stage of 

 Empidonax traillii traillii, are usually lighter on the breast and 

 more yellowish on the posterior lower parts, but some speci- 

 mens are very difficult to distinguish. 



The distinction between Empidonax traillii traillii and 

 Empidonax traillii brewsteri has, of course, long been known. 

 The name Empidonax pusillus (Swainson) was, until Mr. 

 Brewster's investigations,* used for the latter, during which 

 period the name Empidonax traillii or Empidonax pusillus 

 traillii (Audubon) was employed for the eastern bird. The 

 name Empidonax pusillus was taken from Platyrhynchus 

 pusillus of Swainson,! which was described in the following 

 language : 



"Olive brown, beneath yellowish white; wings with two pale 

 bands; tail moderate, even; bill small; head crested. 



Maritime parts of Mexico. 



Total length, 5^; bill, Ym; wings, 2>^; tail, 23^." 



Swainson subsequently identified with this bird a specimen 

 killed at Carlton House, Saskatchewan, and described and 

 figured by him as Tyrannula pusillaX, which is, as already stated 

 by Mr. Brewster, very probably not this species at all, but 

 Empidonax mifiimus. Even if the Tyrannula pusilla of Swain- 

 son be correctly identified as Platyrhynchus pits ill us from Mex- 

 ico, this does not aid in the solution of the identity of the latter, 

 for the availability of the name must in this case be determined 

 from the original description or from an examination of the 

 type. As the above quotation shows, the original description 

 of Platyrhynchus pusillus Swainson, while pointing toward the 

 bird we have here described as Empidonax traillii brewsteri, 

 is not certainly identifiable as such. Professor Alfred Newton 

 made careful search among the Sw^ainson types still remaining 

 in the collection of the mmseum at Cambridge, England, but the 

 type of Platyrhynchus pusillus is not there; nor apparently is it 

 ever likely to turn up elsewhere. Therefore, as has already 



*Auk, XII, Xo. 2, April, 1895, pp. 159-163. 



tPhilosophical Magazine, new series, I, No. V, May, 1827, p. 360. 



tFauna Bor.-Amcr., II, 1831 (1832), p. 144, pi. XLVI, upper figure. 



