PROCEEDINGS 



OF THE 



UNITED STATES NATIONAE MUSEUM. 



1 § 79. 



NOTES 03V THE NESTS AND EOOS OF THE EVOHT NORTH AOIERICAN 

 SPECIES OF EMPIDONACES. 



By T. M. BRE^^^ER. 



In the following paper are given the measurements of all the eggs of 

 the eight species of Empidonax that are in the collections of the Smith- 

 sonian Institution, and also those in my own, and also a few others. 

 Three of these species, IE. minimus^ ohscuruSj and hammondi, so far as 

 is known, have eggs that are uniformly of an unspotted white. If ever 

 spotted, they are so very rarely and so very slightly as hardly to con- 

 stitute really an exception. In another species, Jlavwentris, of which, 

 so far as I am aware, only five or six well-identified sets have been se- 

 cured, at least two well-identified sets have been taken that are entirely 

 of an unsi)otted white color, the others being all more or less spotted 

 and marked. All the remaining four species, traillii, acadiais, piisillus, 

 and difficiUsj have eggs strongly marked, though, among them all, eggs 

 are occasionally found that are of an unspotted white, or marked with 

 very minute spottings. In the following brief mention I chiefly con- 

 fine myself to the size of each egg, its locality, and the authority for its 

 identification, if the record has been preserved. 



Empidonax bammondi, Baird. 



Four eggs in Museum of Comparative Zoology, Cambridge (]S"o. 1G81), 

 from Blue River, Colo., Edwin Carter, measure .02 x .52 ; .00 x .54 ; .02 

 X .52 ; .04 X .53, averaging about .02 x .53.* 



T. M. B.'s cabinet No. 1921. Anderson Elver. MacFarlane. .07x..52; 

 .08 X .51. 



The first set is smaller and more roiuidcd than average eggs of U. 

 wji(imw.s, but they are otherwise indistinguishable. None are spotted. 



Empidonax obscurus, Baird. 



Smithsonian No. 15875. Utah. Eidgway. .71 x .55. Ground-color 

 an immaculate dead white. 



Smithsonian No. 13502. Austin, Nev. Eidgway. .72 x .55 5 .74 x .55. 



Smithsonian No. 2335. Dodge Valley, Utah. McCarty. .70x.55; 

 .72 X .54. 



*I am indebted for these raeasuiciucnts to Mr. ,]. A. Allen. 



Proc. Nat. Mus. 79 1 Ai>B-iB »2», I 879. 



