VIREOSYLVIA. 



343 



12891 



Vireosylvia swai-nsoni. (California.) 



TireosyiTia sivainsoni. 



Vireo swainsoni, Baied, Birds N. Am. 1858, 336 (Pacific coast). 

 Vireo hartramii, Swaikson, V. B. A. II, 1831, 235 (in part ; spec, from 

 I Columbia River ?). 



Hab. United States, from Rocky Mountains to Pacific coast. 



(No. 5,321, % .) Similar to V. gilva, but smaller ; colors paler. Bill more 

 depressed. Upper mandible 

 almost black. Second quill 

 much shorter than 6th. 



(No. 5,521,^ .) Total length, 

 4.75; wing, 2.71; tail, 2.35; 

 difference between 10th quill 

 and longest, .58 ; exposed por- 

 tion of 1st primary, .58, of 2d, 

 1.82, of longest (measured 

 from exposed base of 1st pri- 

 mary), 2.10; length of bill 



from forehead, .56, from nostril, .29, along gape, .65 ; depth of bill, .13 ; tarsus, 

 .70 ; middle toe and claw, .56 ; hind toe and claw, .43. 



In the article on Vireo gilvus, in the Pacific R. R. Report (Birds 

 N. America), I pointed out certain differences between western and 

 eastern specimens, and applied the provisional name of V. swainsoni 

 to the former. An examination of many additional specimens since 

 that time has only tended to confirm the impression of the existence 

 of two species, the differences noted, though apparently slight, 

 being constant and readily appreciable. In the western bird ( V. 

 swainsoni) the bill is darker in color, much smaller, and more de- 

 pressed, the depth at the base being less than the width, instead of 

 being equal to it. The wing is more rounded, the second quill much 

 shorter than the sixth, generally shorter or but little longer than the 

 seventh. In eastern specimens (V. gilva) the second quill is about 

 equal to the sixth. The second quill is about .30 of an inch (or 

 more) shorter than the longest in swainsoni, while in gilva it is 



