THE GENUS VIREO 485 



Phyllomanes, Cab. Arch. f. Naturg. 1847, Bd. i. 321 ; Mas. Hein. 1850, 63 (substituted for 



Vireosylvia). 

 Lanlvireo, Bd. BNA, 1858, 329. (Type Yireo flavifrons V.) 

 Tireonella, Bd. Eev. AB. 1866, 326. (Type Yireo gundlachi Lemb.) 



Bill like that of a Shrike in miniature, moderately or very 

 stout, shorter than the head, compressed at least toward the 

 end, distinctly hooked and notched at the tip, sometimes with 

 trace of a tooth behind the notch of the upper mandible, and 

 usually a nick in the under mandible too. Rictal bristles con- 

 spicuous, and others present among the frontal and mental 

 feathers. Nasal fossae nearly filled with short erect feathers. 

 Toes extensively coherent at base, as explained under head of 

 the family ; lateral toes of unequal lengths ; claws stout, nar- 

 rowly compressed, much curved and acute. Wings at least as 

 long as the tail, more or less rounded ; sometimes much longer 

 and quite pointed ; of ten primaries, the 1st usually evident, 

 though short and spurious, but sometimes (in the section Vireo- 

 sylvia and in Yireo flavifrons) rudimentary and more or less 

 completely concealed (exceptionally obvious even in these spe- 

 cies). Tail short, even, of narrow feathers. Size small ; length 

 usually five or six inches. Coloration simple; above oliva- 

 ceous or grayish, the crown like the back, or ashy (in one case 

 brown, in another black), the under parts white, or white and 

 yellow, or partly olivaceous. Sexes alike indistinguishable; 

 young similar, not spotted or streaked. Migratory in North 

 America. Insectivorous, arboricole. Nest pendulous; eggs 

 white, spotted. 



The Vireos were long supposed to be in the curious case, that 

 some species j)ossessed ten primaries, and others only nine — 

 certainly a remarkable circumstance, considering how constant 

 the number of primaries is among Oscines, and how distinctive 

 of great groups this character is. 



Baird first showed that all the supposed uine-primaried species 

 have really the full number, ten ; the first being reduced to 

 the extreme of the spurious state, in which it is usually entirely 

 hidden from view, and even displaced to the outer side of the 

 next quill, on the base of which it rests like a duplicate of one of 

 the tiny coverts of the point of the pinion. Such is normally 

 the case in Vireo flavifrons, in V. pliiladelphicus, and in all the 

 species of the V. olivaceus group ( Vireosylvia). We have lately, 

 however, discovered that even V. olivaceus may possess an 

 obvious spurious primary, fully exposed in the normal position. 

 Thus, in a specimen before me as I write, kindly submitted to 



