358 



REVIEW OF AMERICAN BIRDS. 



[part I. 



region and a narrow space around eye dull yellowish, in faint contrast to the 

 olive of head. Bill horn color above, paler below ; legs dusky. 



(No. 3,725.) Total length, 4.70 ; wing, 2.40 ; tail, 2.05 ; difference between 

 10th and longest quills, .43 ; exposed portion of 1st primary, .72, of 2d, 1.52> 

 of longest, 4th and 5th (measured from exposed base of 1st primary), 1.90; 

 lengtli of bill from forehead, .45, from nostril, .29, along gape, .60; tarsus, 

 .72 ; middle toe and claw, .50, claw alone, .16 ; hind toe and claw, .45, claw 

 alone, .22. 



The description just given is based upon the type specimen, pro- 

 bably in winter plumage. Spring specimens do not vary materially 

 except in greater purity of white edgings of the feathers. Two 

 Mexican specimens are rather larger, the wing measuring 2.50, the 

 tail 2.30. No other differences are appreciable. In general the first 

 primary is about half the second, sometimes rather less. 



This species is readily distinguished from other Vireos, excepting 

 V. modesfvs, which it greatly resembles in the small bill, form, 

 coloration, and size ; nor indeed is it easy to distinguish them. In 

 mode!<fus, however, the first quill is usually more than half the 

 second, not less ; the wing shorter, and less pointed ; the tail longer. 

 The upper parts are more uniform, not much brighter towards rump 

 and tail. Tlie quite distinct circum-ocular light ring of hutloni is 

 scarcely if at all appreciable. The wide separation geographically 

 is of much importance. 



(3,72.5.) Type. (3,973.) '• Eyes dark brown." 



Vireo l>ellii. 



Vireo hellii, AuD. Birds Am. VII, 1844, 333, pi. 485 (Missouri River).— 

 Cassin, Pr. A. N. Sc. Phila. 1851, 150.— Baikd, Birds N. Am. 1858, 

 337.— ScLATEK, Catal. 1861, 42, no. 258.— Bo.\. Consp. 1850, 330. 



JIab. United States, from Missouri River to base of Rocky Mountains. 



(No. 1,926.) Above olive green, brightest on the rump ; tinged anteriorly with 

 ashy; the top and sides of head ashy, in faint contrast. A line from nostrils 

 to eye (scarcely beyond it), and eyelids very pale yellowish-white ; lores 

 dusky. Under parts, including inner wing, coverts and edge of wing creamy 



