VIREO. 36T 



again as a small yellowish spot above the posterior corner, seems 

 quite peculiar. 



A specimen (male, June 16) from Mazatlan agrees closely in form 

 with the present bird, although rather larger. The first quill is only 

 a little more than half the second. The colors are duller, and the 

 under parts paler ; the white markings are less distinct, owing to the 

 worn condition of the feathers. The extension of the range of the 

 species from Southern Guatemala to Mazatlan is an interesting fact, 

 paralleled by the facts in the case of Hirundo alhilinea, various Tro- 

 chilidae, etc., no specimens of which have hitherto been observed in 

 the intermediate coast of Mexico. 



The type of the species described above has been kindly furnished 

 by Mr. Salvin. 



Vij-eo semijlavus (the type of which I have before me from Mr. 

 Salvin) I can hardly consider as distinct from ochraceus, as it re- 

 sembles it very closely in 

 size, form, and propor- 

 tions. The first quill, in 

 the type, is shorter than 

 in ochraceus — being not 

 quite half the second ; the 

 other quills are as in V. 

 ochraceus. The upper 

 parts are rather brighter 

 green ; the under parts lack the ochrey tinge, and the light markings 

 on the wing are narrower. The aame peculiarities of the eye stripe 

 are seen in both types. The difference of coloration is what might 

 be expected between birds killed in January and in April, and the 

 difference in length of outer quills such as is met with frequently in 

 well established species. 



(No. 428.) Total length, 4.40; wing, 2.10; tail, 1.95; difference between 

 lOth and longest quills, .20 ; exposed portion of 1st primary, .62, of 2d, 1.25, 

 of longest, 5th and 6th (measured from exposed base of 1st primary), 1.60; 

 length of bill from forehead, .54, from nostril, .30, along gape, .60; tarsus, 

 78 ; middle toe and claw, .52, claw alone, .18; hind toe and claw, .44, claw 

 alone, .20. 



A specimen from Merida, Yucatan (April), a locality nearly due 

 north of Lake Peten, and closely related to the region of the latter 

 in its zoological geography, agrees in general characters, but has the 

 outer primary a little more than half the second, although not as 

 long as in the type of ochraceus — about what it is in the Mazatlan 

 specimen. The bill is darker and rather narrower. 



Vireo semiflavuis. 



