twice as long as culmen; tomia straight or gently curved. Nostrils not obviously nearer culmen than tomia. Tarsus longer than lateral toe and claw.
Bill very slender, acute; culmen rather concave at base. Longest secondary acuminate, nearly or quite equal to the primaries in the closed wing. Hind claw little curved, about twice as long as the middle claw. Hind toe and claw longer than middle toe and claw … Motacillidæ.
Bill variously conico-elongate and acute; culmen not concave at base. Longest secondary not acuminate, falling far short of primaries in the closed wing. Hind claw well curved, not nearly twice as long as middle claw; hind toe and claw not longer than middle toe and claw. Gape ample; tongue slightly bifid or brushy, if at all … Sylvicolidæ.
Bill lengthened, very acute, even decurved. Wings and feet as in the last. Gape constricted; tongue generally deeply bifid or brushy … Cærebidæ.
ccc. Bill more or less truly conic, usually short, thick; commissure usually more or less evidently abruptly angulated near the base, or with lobe or tooth further forward. Nostrils obviously nearer culmen than tomia. Tarsus longer than lateral toe and claw.13
Bill stout, tumid, convex in nearly all its outlines; tomia not angulated, but with one or more lobes or nicks in advance of the base. Nostrils placed very high. Other characters much as in Sylvicolidæ. Colors chiefly red and yellow. One genus of … Tanagridæ.
Bill truly conic, much shorter than head, usually with the angulation evident; no lobe along middle of tomia, but usually a notch at end. Nostrils placed very high. Rictal bristles usually obvious … Fringillidæ.
Bill conic, but lengthened, little if any shorter than head; the angulation of the tomia evident; no notch at end. Nostrils high. No rictal bristles … Icteridæ.
bb. Primaries ten.
Otherwise with characters much as in Icteridæ … Sturnidæ.
d. Nostrils concealed with antrorse bristly feathers (except in Psilorhinus and Gymnokitta).14
Base of bill sheathed with antrorse bristly feathers, having lateral branches to their very ends; its tip mostly notched. Basal joint of middle toe united only half-way to the lateral. Sides of tarsus occupied by a lateral groove, mostly filled in with small plates. First primary more than half as long as second. Large,—over seven inches … Corvidæ.
Base of bill with two tufts of bristly feathers, ending in simple filaments without lateral branches, its tip mostly unnotched. Basal joint of middle toe united nearly all its length with the lateral. Sides of tarsus ungrooved. First primary less than half as long as second. Small,—under seven inches … Paridæ.15
dd. Nostrils exposed.
e. Tail scansorial, with rigid acute feathers. Whole bill slender, compressed, acute, decurved, unnotched, unbristled. Outer toe much longer than inner … Certhiidæ.
ee. Tail not scansorial, graduated. First primary not less (generally more) than half as long as the second, and inner toe united to the middle by at least one half (usually more) of the length of its basal joint.
Tarsus with few obscure scutella. Rictal bristles present. Bill stout, but not toothed nor hooked. Wing excessively rounded (fifth, sixth, and seventh primaries longest), much shorter than the long graduated tail. Size small. Plumage brown, unbanded … Chamæadæ.
Tarsus distinctly scutellate. Nostrils wholly exposed, scaled. No rictal bristles, but loral feathers with bristly points. Bill slender, not notched nor hooked. Wings and tail moderately rounded; neither very much shorter than the other. Size small. Color brown, etc., the wings and tail barred or undulated … Troglodytidæ.
Tarsus distinctly scutellate. Nostrils overhung (not concealed) with bristly feathers. Rictal bristles present, strong. Bill powerful, compressed, strongly notched, toothed, and hooked. Wings and tail moderate. Large. Colors black, white, and gray … Laniidæ.
eee. Tail not scansorial. First primary less than half as long as the second,16 or about half as long, in which case the inner toe is cleft nearly to its base (f and ff).
f. Basal joint of middle toe united some distance with the inner, and for half or more of its length with the outer toe.
Basal joint of middle toe shorter than that of inner toe, and wholly adherent to both inner and outer toes. Tarsus longer than middle toe and claw. Gonys more than half the length of the lower jaw. Bill stout, high, compressed; notched and abruptly hooked at tip … Vireonidæ.
Basal joint of middle toe not shorter than that of inner toe; united to the outer for about two thirds, to the inner for about one half, its length. Tarsus not longer than the middle toe and claw. Gonys less than half the length of the under jaw. Bill triangular, much depressed at base, moderately notched, and hooked at tip17 … Ampelidæ.
Basal joint of middle toe shorter than that of the inner toe, united to the outer for about two thirds, to the inner for about one half, its length. Tarsus longer than middle toe and claw. Gonys more than half the length of the under jaw. Bill very weak and slender, little decurved or notched at tip. Very small,—under six inches long. (Tarsi booted in Regulus, distinctly scutellate in Polioptila.) … Sylviidæ.
ff. Basal joint of middle toe quite free from the inner, and not united with the outer more than half-way.
Nostrils linear, low. No bristles or bristly points whatever about the mouth. Wings short, rounded, concavo-convex. Tail very short, nearly concealed by its coverts. Tarsi booted … Cinclidæ.
Nostrils oval. Bristles or bristly points about the mouth. Wings very long and pointed, reaching, when folded, beyond the middle of the short, square, or emarginate tail, and one and a half times or more the length of the latter; tip formed by second, third, and fourth quills; outer secondary reaching only about two thirds way to end of longest primary; spurious quill very short. Tarsi booted … Saxicolidæ.
Nostrils oval. Bristles or bristly points about the mouth. Wings moderate, not reaching, when folded, beyond the middle of the tail, and not over one and a third times as long as the latter; tip formed by third to sixth quill; outer secondary reaching in closed wing three fourths or more the length of the longest primary. Spurious quill longer, sometimes one half the second. Tarsi scutellate in Miminæ, booted in Turdinæ … Turdidæ.
aa. Outside of tarsus covered with two series of scutella,—one lapping entirely around in front, the other entirely around behind, and meeting at a groove on the inside; hind edge blunt. First primary spurious or apparently wanting. Hind claw much lengthened, scarcely curved. Nostrils with antrorse bristly feathers. Bill conico-elongate … Alaudidæ.
B. Clamatores. Outside of tarsus covered with a series of plates variously arranged, lapping entirely around in front and behind, to meet at a groove on the inner side.
First primary lengthened, often longest, at least over two thirds as long as the longest. Bill broad at the base, much depressed, tapering to a fine point, which is abruptly decurved; culmen rounded or flattened; gonys flattened; commissure straight, or nearly so, to the tip. Nostrils small, circular, basal; overhung, but not concealed by bristles.
In the true conirostral or fringilliform genera the under mandible has high strong tomia, bent at an angle near the base; the corresponding portion of the upper mandible is deep, so that the nostrils are nearer the culmen than the tomia. The whole bill is more or less bent in its axis from the axis of the cranial base, so that the palate curves down, or is excavated or, as it were, is broken into two planes meeting at an angle,—one plane the anterior hard imperforate roof of the mouth, the other the back palate where the internal nares are situate (Sundevall). The single North American genus of
These two genera,
With the
In the genus
In
