How to Name the Birds :27
brightly colored birds, there is marked sexual and seasonal variation among Warblers, the male being the brighter in the spring, but often resembling his mate in the fall, when the young bird of the year may differ from both his parents, Thus, in making a ‘key' to our thirty-eight eastern Warblers, the writer found it necessary to represent their difierent plumages by somewhat over one hundred specimens.
External S!rudure.—As in the case of color, Warblers vary so in form that no one description can be given of the family as a whole. The slender-billed species, well represented by the members of the genus Helminfbap/Ii/u and Dmdraira, might be confused with the Vireos, but the bill is more acute and is never distinctly hooked, The flat- billed, Hy-catching species of the genera Wilsmzia and Setup/my might, if the bill alone is considered. be mistaken for true Flycatchers, from which, however, aside from other reasons, they are to be distinguished by their brighter colors. All Warblers have the back of the tarsus thin, not rounded, as in the Flycatchers, and the three outer primaries of nearly equal length.
rippmranre and Habitrt—As might be expected, striking differences in form are accompanied by striking differences in habit. Even among the slender-billed Warblers, some haunt the bushes and sortie the trees, and several may be called terrestrial. The flat-billed species, as has been remarked. are Flycatchers, not, however, of the sedate, automatic, Phtebe type. but of more erratic movement, while the majority are active flute terers—the feathered embodiment of perpetual motion.
Sang.—With some marked exceptions, notably in the genera Gent};- [ypir and Seiurus, the songs of Warblers are rather weak and character- less, and bear a resemblance to one another. which renders them of little assistance to the beginner in identifying their owners. Indeed, com- paratively few field-students can distinguish at once the notes of certain species. Particularly is this true of migrants, which, present only for a brief period in the spring and songless when returning in the fall, are heard, therefore, at intervals of nearly a year
FAMILY 13. PIPITS AND WAOTAILS. Mommi/tidm
Rangn—Of the sixty odd species included in this family, only three are American, two being North, one South American, while the remain- der are distributed through the Old World, except in Polynesia and Aus- tralia, The only species found regularly east of the Mississippi is the American Pipit or Titlark.
SPHIWI.—Th€ Titlark breeds in arctic and subarctic America and southward in the higher parts of the Rocky mountains. It winters from the southern states to Central America. migrating in October and April.
