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.
A. Tail with a broad terminal band abruptly lighter in color than the basal portion, and with a more or less well-defined blackish band across the middle. Nape with metallic reflections.
a. A narrow nuchal band of white; the metallic feathers beneath this, with their outlines distinct, producing a squamate appearance.
1. C. fasciata. Blackish band across the middle of the tail narrow, and badly defined, and concealed by the coverts; terminal portion of the tail much lighter than the basal part. Bill yellow; crissum whitish; hood and anterior lower parts ashy vinaceous-purple; dorsal region ashy.
Bill tipped with black; wing-coverts conspicuously edged with white; back with an olivaceous cast. Wing, 8.80; tail, 6.10; culmen, .75; tarsus, 1.13; middle toe, 1.37; outer, 1.05; inner, .94. Hab. Pacific Province of the United States, south to Guatemala … var. fasciata.
Bill entirely yellow; wing-coverts not distinctly edged with white; back with a bluish cast. Wing, 8.30; tail, 6.20; culmen, .80; tarsus, 1.04; middle toe, 1.27; outer, 1.00; inner, .88. Hab. Costa Rica … var. albilinea.[99]
2. C. araucana.[100] Black band across the middle of the tail as broad as the terminal lighter one, and wholly exposed; terminal portion not lighter than the base. Bill black; crissum deep slate; hood and lower parts deep purplish-vinaceous; dorsal region like the breast. Wing, 8.35; tail, 6.20; culmen, .58; tarsus, 1.13; middle toe, 1.26; outer, .90; inner, .77. Hab. Chile.