SUB-ORDER 
COLUMBAE. 
Cu.—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 toe without membrane 
at the bese. Tarsi mure or less naked ; covered laterally and behind with hexagonal scales. 
The preceding diagnosis expresses sufficiently the chief characters of this sub-order, or rather 
order, divided by Bonaparte into two tribes, one Pleiodi, including Didunculus, of Peale, the 
other Gyrantes, or true doves. The Gyrantes are divided by the same author into Treronidae, 
Columbidae, Caloenidae, and Gouridae, characterized as follows : 
TrERONIDAE.—Bill robust, tumid; rictus ample. Feet short, thick, half feathered ; toes 
fleshy ; claws strong, hooked. ‘Tail feathers, 14. Feathers soft, without metallic lustre ; 
prevailing color green ; wing with a yellow band. The species are frugivorous and arboreal. 
They are confined entirely to the old world, and are especially abundant in the islands of the 
Pacific. 
CotumMprpaE.—Bill horny at the tip. Tail feathers 12; only occasionally 14. Head smooth. 
Universally distributed. 
CALorntpAE.—Bill lengthened ; cere swollen ; cervical feathers elongated, acute, pendulous, 
Dorsal accuminate. Tail feathers 12. The single species, Caloenas nicobarica, confined to the 
Hast India islands. 
Gourman.—Head conspicuously crested ; tail feathers 16. The two species confined to 
New Guinea. 
The bill of the Columbae 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 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 billis 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 Colwmbae in proper sequence and of determining their synonomy 
comparatively easy. He divides the family Colwmbidae, the only one with representatives in the 
new world, into Lopholaeminae, Columbinae, Turturinae, Zenaidinae, and Phapinae, the second 
and fourth alone occurring in North America. They may be briefly distinguished as follows : 
CoLuMBINAE.—Tarsi shorter than the lateral toe ; feathered above. 
ZENAIDINAE.—Tarsi stout, lengthened, longer than the lateral toes ; entirely bare of feathers. 
'The preceding general remarks are taken chiefly from Burmeister, Thiere Brasiliens, Vogel, II, 259. 
