238 GENERAL TRAITS OF WARBLERS 



known specimens, and "carbonata", moreover, may belong to 

 another genus ; while one, olivacea, only lately ascertained to 

 occur within our borders, has been made the type of a separate 

 genus. This leaves twenty-two valid United States species, as 

 given in my "Key" in 1872, there having been no additions 

 since that date to the genus Dendrceca itself, though several 

 other Warblers have in the mean time been discovered and de- 

 scribed. Dendrceca tigrina, made by Baird the type of a distinct 

 genus Perissoglossa in 1865, 1 still retain in this genus, pending 

 the question whether other Warblers may not share its sup- 

 posed peculiarities. The principal extralimital species of the 

 genus are the Cuban D. pityopMla, the Jamaican D. pharetra, 

 the Porto Eican D. adelaidm, and the several species or races 

 related to J), mstiva. 



The beauty and variety of the genus are displayed to best 

 advantage in the woodland of the Eastern United States, where 

 the numerous species are conspicuous ornaments of the forest 

 scene. In most portions of the United States, the Wood- 

 warblers are migratory birds, coming with great regularity iu 

 the spring, each in its own time, abounding for a season, and 

 then passing on to reappear in even greater profusion during 

 the autumn. It is scarcely possible, however, to speak of them 

 collectively in other than very general terms, such is the diflfer- 

 ence they present not only in their movements, but in the minor 

 details of their habits and traits of character. To the regular 

 periodicity of their movements may be ascribed in some mea- 

 sure the constancy of their specific characters, since none of 

 them are long subjected to the modifying influences of particu- 

 lar localities. Some species, like dominica, are quite southerly 

 in their distribution ; a few, like discolor and pin'os, breed south- 

 erly as well as farther north, and are as well known at large 

 during the breeding season as at any other time. Most of them, 

 however, push the spring migration to higher latitudes, scarcely 

 resting content south of the latitude of Massachusetts, unless 

 it be that they are satisfied to nestle upon the higher eleva- 

 tions of the Alleghanies. Few remain with us during the 

 winter, and these only linger along our southern border; but 

 the hardy and resolute Yellow-rumps are an exception to this 

 statement, as they abound over at least the southern half of 

 the United States throughout the most inclement seasons. The 

 rest find more congenial winter homes beyond our border; some 

 in the West Indies, others again in Mexico, and yet others in 



