Part 82

1588. Catharista atrata. Skull and palatine bones. One half natural size.

3369. Pseudogryphus californianus. Skull and palatine bones. One half natural size. Sternum, 3369. One fourth natural size.

260. Rhinogryphus aura. Skull and palatine bones. One half natural size. Sternum, 9007. One fourth natural size.

9007. Sarcorhamphus papa. Skull and palatine bones. One half natural size.]

FAMILY COLUMBIDÆ.—THE PIGEONS.

CHAR. The basal portion of the bill covered by a soft skin, in which are situated the nostrils, overhung by an incumbent fleshy valve, the apical portion hard and convex. The hind toe on the same level with the rest; the anterior toes without membrane at the base. Tarsi more or less naked; covered laterally and behind with hexagonal scales.

The bill of the Columbidæ is always shorter than the head, thinnest in the middle; the basal half covered by a soft skin; the apical portion of both jaws hard; the upper one very convex, blunt, and broad at the tip, where it is also somewhat decurved. There is a long nasal groove, the posterior portion occupied by a cartilaginous scale, covered by a soft cere-like skin. The nostrils constitute an elongated slit in the lower border of the scale. The culmen is always depressed and convex. The bill is never notched in the true Doves, though Didunculus shows well-defined serrations. The tongue is small, soft, and somewhat fleshy.

The wing has ten primaries, and eleven or twelve, rarely fifteen, secondaries; the latter broad, truncate, and of nearly equal length. The tail is rounded or cuneate, never forked.

The tarsus is usually short, rarely longer than the middle toe, scutellate anteriorly, and with hexagonal plates laterally and behind; sometimes naked. An inter-digital membrane is either wanting entirely, or else is very slightly indicated between the middle and outer toes.

The valuable monograph of Bonaparte in the second part of Conspectus Avium renders the task of arranging the American Columbidæ in proper sequence and of determining their synonomy comparatively easy. He divides the family into Lopholæminæ, Columbinæ, Turturinæ, Zenaidinæ, and Phapinæ, the second and fourth alone occurring in North America. They may be briefly distinguished as follows:—

=Columbinæ.= Tarsus shorter than the lateral toe; feathered above.

=Zenaidinæ.= Tarsus longer than the lateral toes; entirely bare of feathers.

SUBFAMILY COLUMBINÆ.

CHAR. Tarsi stout, short, with transverse scutellæ anteriorly; feathered for the basal third above, but not at all behind. Toes lengthened, the lateral decidedly longer than the tarsus. Wings lengthened and pointed. Size large. Tail-feathers twelve.

This section of doves embraces the largest North American species, and among them the more arboreal ones. The genera are as follows:—

=Columba.= Head large; tail short, broad, and rounded.

Outer toe much longer than the inner; bill rather short, stout …

Columba.

Outer toe scarcely longer than the inner; bill lengthened, compressed …

Patagiœnas.

=Ectopistes.= Head very small; tail much lengthened, cuneate.

GENUS COLUMBA, LINNÆUS.

Columba, LINNÆUS, Syst. Nat. 1735. (Type, Columba livia, L.)

GEN. CHAR. Bill stout and rather short; culmen from the base of the feathers about two fifths the head. Lateral toes and claws about equal, reaching nearly to the base of the middle claw; the claws rather long, and not much curved. Tail rather short, rounded, or nearly even; as long as from the carpal joint to the end of secondaries in the closed wing. Second and third quills longest.

Columba fasciata.]

The genus Columba, as characterized above, includes the C. livia, or domestic Pigeon, the differences between it and the American forms being very slight. Reichenbach and Bonaparte separate the North American birds from Columba, under the name of Chlorœnas, while C. leucocephala and a near ally of the West Indies (C. corensis) have been placed in the subgenus Patagiœnas, Reichenbach.

The variations of form among the numerous American members of Columba are more with the species, however, than with groups, and withal are so exceedingly slight that an attempt at subdividing the genus is scarcely justifiable. They may be arranged by the style of coloration as follows. None of the American species have the forepart of the neck metallic, as in the European species, or Columba proper, as restricted, and in which these metallic feathers have the fibres loose and blended, instead of being compact; the feathers also have a well-defined squamate arrangement in nearly or quite all the American Columbæ.

Species and Varieties.