[Illustration: FOOT OF THREE-TOED WOODPECKER.]
Characters the same as those of the Order.
Order XVI. Goatsuckers, Swifts, and Hummingbirds. MACROCHIRES.
Bill, in the Goatsuckers and Swifts, small; mouth large; in the Hummingbirds, bill long, slender, needle-like; wings and tail variable; feet, in all three groups, small and weak. Color, in Goatsuckers, mixed brown, buff and black; in Swifts, black and white; in Hummingbirds, usually shining green above with resplendent throat-patches of varied hues.
Family 44. GOATSUCKERS, ETC. Caprimulgidæ.
Feet usually small and weak; toes, three in front, one behind; middle toe-nail pectinate or combed; bill small; mouth very large and usually beset by long bristles.
Bill small, triangular when seen from above; mouth large, no bristles; tail variable, in _Chætura_ with projecting spines; wings long and narrow; feet small and toes short; plumage usually dark.
[Illustration: RUBY-THROATED HUMMINGBIRD.]
Bill long and slender; feet slender; wings large and pointed; tail exceedingly variable, often assuming the most striking shapes.
Order XVII. Flycatchers, Jays, Blackbirds, Finches, Swallows, Warblers, Thrushes, and Other Perching Birds. PASSERES.
(18 families, about 325 species and 226 subspecies.)
Bill, wings, and tail variable; feet with four toes not connected, the hind-toe as long as the middle one; its nail generally longer than that of the middle toe. This Order contains more species than the remaining sixteen Orders put together. In it will be found over 80 per cent. of the birds commonly seen by field students. It is difficult of definition, but almost any small perching bird may, with more or less certainty, be referred to the _Passeres_.
[Illustration: FOOT OF ROBIN.--(a typical Passerine foot.)]
Bill broad, flat, hooked at tip, its base with bristles; wings rather pointed, the second to fourth primaries longest; tarsus rounded behind as well as in front; feathers of crown generally somewhat lengthened, forming when erected, a small crest; pose, when perching, erect; food of insects usually captured on the wing; voice generally unmusical.
Hind toe-nail much lengthened; bill rounded, straight; tarsus rounded behind as well as in front; our species with a tuft of feathers on either side of the head; outer primary short or rudimentary; walking birds, singing while on the wing.