SYLVICOLID.E — THE WARBLERS. I77 



Family SYLVICOLIDiE. — The Warblers. 



Tlie Sylvicolidw are essentially characterized among the Oscines with nine 

 primaries, by their small size, the usually slender and conical insectivorous 

 bill, shorter than the head, without angle in the gape near the base ; the toes 

 deeply cleft so as to leave the inner one free almost to its very base (except 

 in Mniotilkw), etc. The shallow notch at the end of the tongue, instead of 

 a deeply fissured tip, distinguishes the family from the Ccerebidce, to some of 

 which there is otherwise so great a resemblance. The absence of abrupt 

 hook and notch in botli mandibles separates it from such of the Vireonidcv 

 as have nine primaries. 



The American Motncillidm are distinguished from the Sylvicolidoi by 

 the emargination of the outer and the great elongation of the inner sec- 

 ondaries, as well as by otlier features referred to under that family. 

 Anfhus, in particular, differs in the lengthened and sliglitly curved hind 

 claw. There is little difficulty in distinguisliing the Sylvicolidce, however, 

 from any families excepting the slender-billed forms of the Tanagridce-, as 

 CJdorospingns, Neraosia, Chlorochrysa, etc., and the .conirostral Cmrebidcc. 

 In fact, some ornithologists are inclined to include all three of the families 

 thus mentioned in one, from the difticulty of marking their boundaries 

 respectively. 



In fact, we are of the opinion that no violence would be done by adopt- 

 ing this view, and would even include witli the above-mentioned families 

 the Fringillidce also. The order of their relation to one another would be 

 thus: Fringillidcc , Tanagridce, Sylvicolidm, Ccercbidm ; there being scarcely 

 any break in the transition between the two extremes, unless there are 

 many genera referred to the wrong family, as seems very likely to be the case 

 with many included in the Tanagridce. The fringilline forms of the latter 

 family are such genera as Baarremon and Arremon, they being so closely 

 related to some fringilline, genera by so many features — as rounded concave 

 wing, lax plumage, and spizine coloration — as to be scarcely separable. 

 Either these two families are connected so perfectly by intermediate forms 

 as to be inseparable, or the term TaAiagridai covers too great a diversity of 

 forms. With the same regularity that we proceed from the Fringillidm to 

 the typical forms of the Tanagridoi (Fyranga, Tanagra, CaUiste, etc.), Ave 

 ])ass down the scale from these to the Sylvicolidw ; while between many 

 genera of the latter family, and others referred to the Ca'rebidfe, no differ- 

 ence in external anatomy can be discovered, much less expressed in a 

 description. 



In the following synopsis we attempt to define the higher groups of the 

 ^Sylvicolida% although in the large number of species and their close relation- 

 ships it is very difficult to express clearly their distinctive features. 

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