150 



U. S. p. n. K. KXP. AND SURVEYS — ZOOLOGY — GENERAL REPORT. 



List of specimens. 



CHOKDEILES, Swaiason. 



SwAiNsoN, Fauna Bor. Amer. II, 1831, 490. 



Ch. Bill very small, the gape with very short feeble bristles. Wings very long and pointed, with the first quill nearly or 



quite equal to the second, and the primaries not emarginated on the inner edge. Tail long ; slightly forked in the North American 

 species ; plumage>ather compact. 



The described North American species of this genus are three in number, tlie smaller readily 

 distinguishable by the rounded rufous spots on the webs of the quills, (C texensis.) The others 

 are larger and more closely related. 



Comparative measurements of species. 



