SYLVIID.E — THE SYLVIAS. 



69 



Family SYLVIIDiE. — The Sylvias. 



Cr 



I'nAR. Bill much shorter than head, slen«ler, broad, and depressed at the base, distinctly 

 notched and deeurved at the tip. Cidmen sharp-rid<red at base. Frontal feathers reachinj^ 

 to the nostrils, which are oval, with membrane above, and overhunjr — not concealed — 

 by a few bristles or by a feather, Itictal bristles cxtendinjj beyond nostrils. Tarsi booted 

 or scutellate. Basal joint of middle toe attaeiied its whole length externally, half-way 

 internally. Primaries ten ; spurious primary about half the second, which is shorter than 

 the seventh. Lateral toes equal. 



The birds of this family are readily distinguished from the ParUhv by the 

 slender bill, notched and deciirved at tip ; much bristled ga^^e, sharp-ridged 

 culmen, exposed oval nostrils, less adherent toes, etc. They are much smaller 

 than the TurdUlw and Saj-icolkicv, with much more slender, depressed bill, 

 longer rictal bristles, etc. The short outer primary, with the primaries ten 

 in number, distinguish them from the Si/lvieolida'. 



The following synopsis will serve to characterize the American forms of 

 their res[)ective subfamilies. The species are all among the most diminutive 

 in size with the exception of the Humming-Birds : — 



A. Wings long'T than the nearly even and emarginate tail. Scutella; of tarsus 

 scarcely or not at all appreciable. General color olivaceous above. Xo white on 

 tail. 



Nostrils naked. ScutelUc distinct on inner n\ce of tarsus only. Head plain. 



Sylviince. 

 Nostrils overhung by bristly feathers. Scutellae of tarsus not appreciable. 

 Head with a colored central crest Regulince. 



B. Wings about equal to the graduated tail Tarsal scutellae distinct. Above 

 bluish ; tail with white spots or patches. 



Nostrils uncovered. Head plain ; either bluish or black above. Poliojyf il ince. 



Subfamily SYLVIINiE. 



Char. Size and form of St/h-icolhicp, but with a spmious first primary about one thinl 

 the swond quill. Wings cons''derably longer than the nearly even or emarginate tail. 

 Feathers of frontal region with bristly points; but not covering the nostrils. Tarsi 

 scutellate anteriorly, but indistinct externally (Characters drawn with reference to tlie 

 American form.) 



The introduction of this sul)f{imily into the jiresent work is required to 

 accommodate a species of PhjiIIoimcuMe collected on the Yukon by the Rus- 

 sian Telegraph Expedition, the first known instance of the existence in North 

 America of a group of birds characteristic of the northern parts of the Old 

 World. Among the smallest of the class, they are eminently sociable, and 

 feed entirely on insects, which they capture mostly 0:1 the whig, like fly- 



