250 COLUMBINE. 



Mr. Swainson and other ornithologists have converted it into 

 several generic groups, such as Vinago, including the thick- 

 billed sj^ecies ; Ptilonopus, Columba, Turtur, Ectopistes, Pe- 

 ristera, and others, characterized by differences in the wings and 

 tail, and Loj^hyrus, formed by Vieillot of the Great Crowned 

 Pigeon. The latter seems to connect this family with the 

 Cracinae, which belong to the Gallinaceous order, while other 

 groups manifest an affinity to the Partridges and allied genera. 



The Pigeons vary much in form, some having the body full, 

 others slender, while the tail is very short, moderate, or greatly 

 elongated. In all however, the head, Figs. 52, 53, 54, is small, 

 oblong, compressed, w^th the forehead rounded, a circumstance 

 depending partly upon the form of the skull, and partly upon the 

 absence of feathers at the base of the bill. The latter organ is 

 characterized more especially by having the nasal membrane 

 bare, generally scurfy, fleshy and tumid, with the narrow longi- 

 tudinal nostrils placed under its anterior margin. It varies in 

 size, but the upper mandible has its ridge always obliterated 

 at the base by the encroachment of the nasal membranes, and 

 its extremity horny, arched or convex, more or less compressed, 

 with a blunt thin-edged point. The tongue is fleshy, tapering 

 to a point, and triangular in its transverse section. The throat 

 is very narrow. The oesophagus, PI. VII, Fig. 1, a, ^, c, c?, 

 e^ f^ g^ is of moderate width, but expanded, or opening into a 

 large crop, c, (?, e^ /, placed on the lower part of the neck and 

 the fore part of the breast, and terminates below in an oblong 

 proventriculus, g^ completely surrounded w4th large oblong glan- 

 dules. The stomach, /^, «', y, A*, /, is a powerful gizzard of a 

 somewhat rhomboidal form, and furnished with two very thick 

 lateral muscles, ?, y, inserted into two tendinous centres, /, with 

 an inferior thinner muscle, Ic^ inserted into the same tendons. 

 The middle coat is thick and somewhat cartilaginous ; the inner 

 or cuticular with two thick elliptical, transversely rugous plates, 

 the parts opposite the edges of the organ thinner and also ru- 

 gous. The intestine, m^ n^ o, p^ ^, r, is long and slender ; the 

 coeca, Fig. 4, c, ^, very small and cylindrical ; the rectum, b, c, 

 very short, and but slightly enlarged. 



The tarsi are generally short and stout, either scutellate or 

 feathered. The foot, Figs. 50, 51, is of that kind equally adapted 



