494 BIRDS OF ILLINOIS. 



ORDER COLTJMB.ZE. THE PIGEONS on DOVES. 



CHAR. Basal part of the bill tumid and covered with a soft skin, in which are situated 

 the narrow, longitudinal nostrils, overhung by a valve-like scale or covering; terminal 

 portion of the bill hard; the culmen more or less strongly arched. Hind toe usually in- 

 cumbent, and front toes generally cleft to the extreme base. Plumage peculiarly dense, 

 the feathers without aftershafts, and very easily detached from the skin. Primaries ten; 

 secondaries, eleven to fifteen: rectrices, twelve to fourteen. 



The number of families composing this order is at present some- 

 what uncertain. Whatever the number, however, America possesses 

 but one, the Columbidce, or true Pigeons, whose characters are as 

 follows : 



FAMILY COLUMBID-aE. THE PIGEONS. 



"CHAE. 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 Columbidce is always shorter than the head, thin- 

 nest 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. 



