330 SYSTEMATIC SYNOPSIS. — PASSEEES—OSCINES. 



which the 1st is short (one-half to one-fourth the second), or spurious, or apparently wanting 

 (heing rudimentary and displaced). Size small, under 7 inches; coloration simple, mostly and 

 oftenest greenish ; young not spotted or streaked. 



This family was formerly united with the next (Laniidce), chietiy on account of the 

 resemhlance in the shape of the hill of certain species to that of the shrikes ; but the likeness 

 is never perfect, and there are other more important characters, especially in the structure of 

 the feet, by which the two groups may be discriminated. The Vireonidce are peculiar to 

 America ; they are a small family of five or six genera and nearly seventy recorded species, 

 of which about five-sixths appear to be genuine. The typical and principal genus, Vireo, con- 

 taining nearly thirt.y species, is especially characteristic of North America, though several species 

 occur in the West Indies and Central America; one genus and species, Laletes osburni, is 

 exclusively West Indian ; the rest — Cydarhis, Hylophilus, Vireolanms, and Neochloe — are, 

 with one exception. South and Central American. In further illustration of the characters of 

 the group, I ofier some remarks under the head of the only genus with which we have to do in 

 the present connection. 

 59. VIR'EO. (Lat. vireo, I am green or flourishing.) Greenlets. 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 vnth 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 fi-ontal 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, narrowly compressed, much curved and 

 acute. Wings at least as long as the tail, more or less rounded ; sometimes much longer and 

 quite pointed ; of 10 primaries, the 1st usually evident, though short and spurious, but some- 

 times (in the section Vireosylvia and in Fireo ^aw/rows) rudimentary and more or less com- 

 pletely concealed (exceptionally obvious even in these species). Tail short, even, of narrow 

 feathers. Size small ; length usually five or six inches. Coloration simple ; above olivaceous 

 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 quite indistinguishable ; young 

 similar, not spotted or streaked. Migratory in N. Am. Insectivorous, arboricole. Nest pen- 

 dulous ; eggs white, spotted. 



The numerous species of this genus have been divided into several groups, but no violence 

 ■wall be done by considering them all as Vi7-eo — in fact, it is difficult to do otherwise. For 

 even the seemingly substantial division into two genera, according as there is an evident 

 spurious 1st primary or apparently none, separates species, like gilvus and philadelphicus, 

 hardly otherwise specifically distinguishable ; while another division into two genera, according 

 to the shape of the Mangs and length of the spurious 1st primary or its absence, is subject to 

 some uncertainty of determination, and unites species, like olivaceus and flavifrons, most dis- 

 similar in other respects. The fact is, that almost every single species of Vireo has its own 

 peculiar form, in shape of bill, proportions of primaries, etc., and these details cannot well be 

 considered as of more than specific value. These slight diiferences are perfectly tangible and 

 surprisingly constant, rendering the determination of the species comparatively easy, though 

 these birds bear to each other a close general resemblance in size and color. They are all more 

 or less olivaceous above, sometimes inclining to gray or plumbeous, with the crown either like 

 the back, or else ashy, — in one species, however, brown, and in another black ; and white or 

 whitish below, usually more or less tinged with yellow. The coloration is very constant, the 

 sexes being indistinguishable, and the young dififering little, if at all, from the adults. All are 

 small birds, — about 5 or 6 inches long. As a group the student will probably have no diffi- 

 culty in recognizing them by the foregoing diagnosis, as the character of the feet seems to be 

 peculiar, among N. Am. birds, and is at any rate diagnostic when taken in connection with the 



