Pipilo, Vieillot, Analyse, 1816 (Agassiz). (Type, Fringilla erythrophthalma, Linn.)
Pipilo fuscus.
5559 ♂
Gen. Char. Bill rather stout; the culmen gently curved, the gonys nearly straight; the commissure gently concave, with a decided notch near the end; the lower jaw not so deep as the upper; not as wide as the gonys is long, but wider than the base of the upper mandible. Feet large, the tarsus as long as or a little longer than the middle toe; the outer lateral toe a little the longer, and reaching a little beyond the base of the middle claw. The hind claw about equal to its toe; the two together about equal to the outer toe. Claws all stout, compressed, and moderately curved; in some western specimens the claws much larger. Wings reaching about to the end of the upper tail-coverts; short and rounded, though the primaries are considerably longer than the nearly equal secondaries and tertials; the outer four quills are graduated, the first considerably shorter than the second, and about as long as the secondaries. Tail considerably longer than the wings, moderately graduated externally; the feathers rather broad, most rounded off on the inner webs at the end.
Pipilo erythrophthalmus.
The colors vary; the upper parts are generally uniform black or brown, sometimes olive; the under white or brown; no central streaks on the feathers. The hood sometimes differently colored.
In the large number of species or races included in this genus by authors, there are certain differences of form, such as varying graduation of tail, length of claw, etc., but scarcely sufficient to warrant its further subdivision. In coloration, however, we find several different styles, which furnish a convenient method of arrangement into groups.
Few genera in birds exhibit such constancy in trifling variations of form and color, and as these are closely connected with geographical distribution, it seems reasonable to reduce many of the so-called species to a lower rank. In the following synopsis, we arrange the whole of North American and Mexican Pipilos into four sections, with their more positive species, and in the subsequent discussion of the sections separately we shall give what appear to be the varieties.