SETOPHAGA. MYIOBORUS. 413 



Immature male. Similar to the adult female but darker on the 

 back and the yellow portions of the plumage replaced by orange. 



The specimen described above was collected at Bartica in 1911. 



Breeding-season, Unknown in British Gruiana. 



Nest. Unrecorded in British Guiana. 



Eggs. Undescribed from British Gruiana. 



Range in British Guiana. Mount Horaima, Bartica {McConnell 

 collectioii) ; Mount Roraima {Whitely). 



Eictralimital Range. Trinidad, Margarita Island, Venezuela, 

 Ecuador, Colombia, Central America, West India Islands, to 

 North America. 



Habits. According to Schomburgk (Reis. Guian. iii. p. 667) 

 this species is an autumnal migrant in British Guiana and inhabits 

 the woods near Mount Roraima. 



The " Arekunas " call it Pairiha. 



Mr. J. J. Quelch found this bird on the slopes around Mount 

 Roraima and states that there was nothing to show whether it was 

 a migrant or not {cfr. Timehri (2) x. p. 26,1, 1896). 



Genus MTIOBOEUS Baird. 



Myioborus Baird, Keview Amer. B. p. 237, 1865. Type M. verticalis 

 (Lafr. & d'Orb.). 



This genus differs from Setophaga chiefly in the more rounded 

 and graduated tail and the longer rictal bristles. The bill is 

 depressed, the width at the base being about two-thirds the length 

 of the exposed culmen. The wing is rounded, the second, third, 

 fourth, and fifth primaries longest, and the first about equal to the 

 seventh. The tail is rounded at the tip and slightly graduated, 

 the outer feather on each side being 56 mm., and nearly equal in 

 length to the wing. The tarsus is about twice the length of the 

 exposed culmen. Coloration : male and female similar. 



Key to the Species. 



A. Back dark slate-grey ; cA)wn of head 



dark chestnut; chin and throat 



black M. pallidiventris, p. 414. 



B. Back dark bronze-brown ; crown of 



head pale chestnut; chin and 



thi-oat orange-yellow M. castaneicapillus, p. 415. 



