255 



COLUMBA. DOVE. 



The species of which the genus Cokmiba is composed, al- 

 though very numerous, extensively distributed over the globe, 

 and presenting considerable differences in the texture of their 

 plumage, agree in possessing the folloAving general characters. 



Bill shortish, rather slender, straight, compressed. Upper 

 mandible furnished at the base with two soft tumid, bare sub- 

 stances, placed over the nostrils, the dorsal outline straight for 

 one-half of its length, arcuato-declinate towards the end, the 

 sides convex, the edges nearly straight and soft for two-thirds 

 of their length, then decurved, direct, and sharp, the tip obtuse 

 and edged. Lower mandible at its base wider than the upper, 

 its crura slender and elastic, the angle long, obtuse, the dorsal 

 outline short and slightly convex, the sides at the base erect, 

 towards the end convex, the edges soft at the base, towards the 

 end hard, sharp and slightly inflected, the tip obtuse but 

 edged. 



Mouth narrow ; mandibles internally concave. Palate nar- 

 row, with two longitudinal ridges of skin diverging backwards, 

 the space exterior to them ascending. Posterior aperture of 

 the nares linear-oblong, smooth -edged, its anterior slit papillate 

 on the edges, and with a series of small blunt papillae on each 

 side. No transverse flaps on the palate. Tongue sagittate, 

 narrow, tapering to a point, triangular in its transverse section, 

 with a medial groove above, papillate at the base, horny be- 

 neath towards the end. There are two masses of mucous crypts 

 in the angle of the lower jaw ; also a series on the lower side 

 of the tongue on each side towards the base. Aperture of the 

 glottis defended by acute papillae. 



(Esophagus, PL VII, Fig. 1, a, b, c, immediately dilated, 



