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.
A. Sides and lower tail-coverts rufous, in sharp contrast with the clear white of the abdomen. Tail-feathers with whitish patch on end of inner webs.
a. Head and neck black, sharply defined against the white of breast. Rump olive or blackish.
1. P. maculatus. White spots on tips of both rows of wing-coverts, and on scapulars. No white patch on base of primaries. Hab. Mexico, and United States west of the Missouri. (Five races.)
2. P. erythrophthalmus. No white spots on wing-coverts, nor on scapulars. A white patch on base of primaries. Hab. Eastern Province of United States. (Two races.)
3. P. macronyx.18 Scapulars and wing-coverts (both rows) with distinct greenish-white spots on tips of outer webs.
4. P. chlorosoma.19 Scapulars and wing-coverts without trace of white spots. Hab. Table-lands of Mexico. (Perhaps these are two races of one species, macronyx.)
b. Head and neck ashy, paler on jugulum, where the color fades gradually into the white of breast. Rump and upper tail-coverts bright rufous.
5. P. superciliosa.20 An obsolete whitish superciliary stripe. Greater wing-coverts obsoletely whitish at tips; no other white markings on upper parts, and the tail-patches indistinct. Hab. Brazil. (Perhaps not genuine Pipilo.)
B. Sides ashy or tinged with ochraceous; lower tail-coverts ochraceous, not sharply contrasted with white on the abdomen, or else the abdomen concolor with the side. Head never black, and upper parts without light markings (except the wing in fuscus var. albicollis).
a. Wings and tail olive-green.
6. P. chlorurus. Whole pileum (except in young) deep rufous, sharply defined. Whole throat pure white, immaculate, and sharply defined against the surrounding deep ash; a maxillary and a short supraloral stripe of white. Anterior parts of body streaked in young. Hab. Western Province of United States.
b. Wings and tail grayish-brown.
7. P. fuscus. A whitish or ochraceous patch covering the throat contrasting with the adjacent portions, and bounded by dusky specks. Lores and chin like the throat. Hab. Mexico, and United States west of Rocky Mountains. (Five races.)
8. P. aberti. Throat concolor with the adjacent portions, and without distinct spots. Lores and chin blackish. Hab. Colorado region of Middle Province, United States. (Only one form known.)
After a careful study of the very large collection of Black-headed Pipilos (leaving for the present the consideration of those with olive-green bodies) in the Smithsonian Museum, we have come finally to the conclusion that all the species described as having the scapulars and wing-coverts spotted with white—as arcticus, oregonus, and megalonyx, and even including the differently colored P. maculatus of Mexico—are probably only geographical races of one species, representing in the trans-Missouri region the P. erythrophthalmus of the eastern division of the continent. It is true that specimens may be selected of the four races capable of accurate definition, but the transition from one to the other is so gradual that a considerable percentage of the collection can scarcely be assigned satisfactorily; and even if this were possible, the differences after all are only such as are caused by a slight change in the proportion of black, and the varying development of feet and wings.
Taking maculatus as it occurs in the central portion of its wide field of distribution, with wing-spots of average size, we find these spots slightly bordered, or at least often, with black, and the primaries edged externally with white only towards the end. The exterior web of lateral tail-feather is edged mostly with white; the terminal white patches of outer feather about an inch long; that of inner web usually separated from the outer by a black shaft-streak. In more northern specimens the legs are more dusky than usual. The tail is variable, but longer generally than in the other races. The claws are enormously large in many, but not in all specimens, varying considerably; and the fourth primary is usually longest, the first equal to or shorter than the secondaries. This is the race described as P. megalonyx, and characterizes the Middle Province, between the Sierra Nevada of California and the eastern Rocky Mountains, or the great interior basin of the continent; it occurs also near the head of the Rio Grande.
On the Pacific slope of California, as we proceed westward, we find a change in the species, the divergence increasing still more as we proceed northward, until in Oregon and Washington the extreme of range and alteration is seen in P. oregonus. Here the claws are much smaller, the white markings restricted in extent so as to form quite small spots bordered externally by black; the spots on the inner webs of tail much smaller, and even bordered along the shaft with black, and the outer web of the lateral entirely black, or with only a faint white edging. The concealed white of the head and neck has disappeared also.
Proceeding eastward, on the other hand, from our starting-point, we find another race, in P. arcticus, occupying the western slope of the Missouri Valley and the basin of the Saskatchewan, in which, on the contrary, the white increases in quantity, and more and more to its eastern limit. The black borders of the wing-patches disappear, leaving them white externally; and decided white edgings are seen for the first time at the bases of primaries, as well as near their ends, the two sometimes confluent. The terminal tail-patches are larger, the outer web of the exterior feather is entirely white except toward the very base, and we thus have the opposite extreme to P. oregonus. The wings are longer; the third primary longest; the first usually longer than the secondaries or the ninth quill.
Finally, proceeding southward along the table-lands