Common Pigeon. 21 



much shorter but also stouter transverse process limits the iliac 

 fossae^ into relation with which the superior lobe of the kidney 

 and the lower end of the lung come^ from the Hrue pelvis/ The 

 iliac bones have their internal margins in apposition or anchylosed 

 with the outer ends of transverse processes of the sacral 

 vertebrae; they anchylose with ossa pubis and ischii to form 

 the acetabular annulus, and with the ossa ischii, as usual in Birds, 

 to form the sacroischiatic foramen which is homologous with the 

 sacroischiatic notch of anthropotomy. In the Pigeons the ossa 

 pubis do not ordinarily coalesce with the ossa ischii, so as to con- 

 vert the notch for the tendon of the obtusator internus, which 

 lies immediately below the sacroischiatic foramen, into a foramen 

 also. Neither do they coalesce with them, as they do in some 

 birds, posteriorly to this point, so as to form a ' foramen ovale/ 

 The iliopectineal spine, which is well developed in the Rasores, 

 is absent in the Columbidae. The caudal vertebrae, which are 

 not pneumatic, are seven in number, counting the compound os en 

 charrue which supports the uropygial gland and certain of the tail 

 feathers, the rectrices, as one. These vertebrae possess considerable 

 mobility, having no zygajiophyses developed on their neural 

 arches, and being articulated simply by ball and shallow socket 

 joints on their centra and intercentral fibrocartilaginous discs. 

 The pelvis and coracoids ai-e pneumatic, but the furculum and 

 scapulae are not, and it is only in adult birds, either of the Fowl 

 or the Pigeon tribes, that the coracoids become so. The humerus 

 is the only bone in either limb which is pneumatic. The coracoid 

 is exceedingly strong, and the keel of the sternum very deep, as 

 if to compensate for the feebly-developed furculum. The muscular 

 ridges for the origin of the second pectoral muscle, tlie chief 

 elevator of the humerus, are well marked both upon the keel 

 and upon the body of the sternum. The sternum has a wide 

 lateral emargination homologous with the exterior emargination 

 in the Rasorial sternum, but it presents only a small fontanelle 

 to correspond with the deeper and more internally-placed emar- 

 gination of those birds. The grooves for the reception of the 

 articular ends of the coracoids meet anteriorly, and there is no 

 downward prolongation of the cpisternum between those bones 

 as in the Rasores. On either side of the middle line of the cpister- 

 num, a large pneumatic foramen is seen entering the bone ; other 



