BIRDS OK NOKTII AND MIDDLE AMERICA. (>^.^3 



usually alike or nearly so and youn- not materially different fr..n, 

 adults', except sometimes in EeguU^ and rolioptilina'. 



7^,,^,^^._Northern Hemisphere in general and oreatcr part of Neo- 

 tropical Region, but most numerously represented in tiic Pala-ar-tic 

 Rco-ion. (Numerous genera and species.) 



The above diagnosis is based on the forms included under the 

 Sylviidw by Mr. Seebohm," together with the genera Regulus and 

 mioptUa, which I am unable to separate satisfactorily. Certainly 

 there is less structural difference between Regulm and Re<jnloidc.^ on 

 the one hand than between the latter and Sylvia on the other, Acan- 

 thopnmste and other intermediate genera leading directly iromRg^dns 

 toward Sijlvia; consequently I can see no reason for separatmg Jieg- 

 nlus from the Sylviida?, much less for referring it to the Pandas, as 

 has been done by some authors.^ 



As to the exclusively American genus PoUoj^tlhi, I am still in 

 doubt whether it snould be placed anrong the Sylviida?. Its refer- 

 ence to the family Muscicapidte has been suggested by two authors,'' 

 to the Mimidai by another;'^ the latter disposal of it I at one time 

 favored, but after carefully reconsidering the question I am con- 

 vinced that there is no group to which it can properly be referred 

 unless to the Sylviida?, the only alternative being the recognition ot a 

 separate family (Polioptilid*). . i --j 



The only American groups with which any member ot the bylvudre 

 (as here defined) are likely to be confounded are the Paridas Turdidte, 

 Mniotiltida?, and Vireonidai. From the first the Sylviidai differ in 

 more slender and notched bill, sharply ridged culmen, longitudinal 

 and operculate (usually exposed) nostrils,^ distinct rictal bristles less 

 coherent toes, etc.; from the second by the unspotted plumage of the 

 young- from the third by the obvious (though sometimes minute) 

 tenth primary, this being rudimentary and concealed in Mniotiltid^; 

 and from the fourth by the different structure of the toes, while the 

 species of Sylviidre which most resemble certain Vireonida' moreover 

 have the acrotarsium booted. 



Of the so-called subfamilies defined below, the Phylloscopina' are 

 so nearly peculiar to the Old World that only a single species, ot 

 northeastern Asia, occurs in western Alaska, no other portion ot the 

 American continent having a representative of the group. The sub- 



fl Cat. Birds Brit. Mus.,v, 1881, 1-145. 



'. For example, Gadow, in (^at. Birdn Brit. Mas., viii, 1883, <9-8b, Seeboluu, ll..t. 

 Brit Birds, i, 1883, 451, 452, an.l Ilelln.ayr, Tierreich, 18, Lief., 1903, /-15. 



oSharpe, Cat. Birds, Brit. Mas., x, 1885, 440, and Srlater, Ar-entnu- Ornithol-w, 



i, 1888, 12. 



<iSteineKer, Standard Nat. Hist., iv, 1885, 504. , , , , 



e\i the nostrils are hi.lden by feathers in Sylviid.-,. the tarsi are booted (e. g. 



Rtgulus). 



