328 ACCIPITRES. 



sisted of two pieces united together ; the keel much 

 higher in the anterior and middle parts than at the 

 posterior extremities. The sides are a little concave, 

 and the ribs vary from five to seven ; the posterior 

 edge generally nearly straight, with a lateral hole in 

 each angle, but these are often nearly, and sometimes 

 wholly, obliterated by bone. There is not, even in 

 young stages of the more typical birds, any appear- 

 ance of distinct bones forming the sternum, as there 

 are in birds of some other orders, though the process 

 of ossification begins at several points, and proceeds 

 regularly till completed. 



The coracoids are shorter than the sternum, but 

 very strongly formed, and their internal angles, where 

 they are attached to the sternum, often meet each 

 other. The clavicle forms a complete arch, more or 

 less depressed toward the centre, having its depth 

 placed in the direction of the strain ; of nearly equal 

 strength throughout its length in the falcons, which 

 are the birds of most rapid and continuous flight, but 

 diminished toward the middle in most of the others ; 

 and firmly united at both extremities to the scapulars 

 and the coracoids. 



The scapulars are a little longer than the sides of 

 the sternum, oval in their section, slightly curved, 

 pointed at their extremities, and firmly united with 

 the coracoids and clavicle at the angle of the shoulder, 

 a little above the articulation of the humerus, to which 

 they afford a very firm point of support, and to the 

 tendon of whose elevating muscle they furnish a very 

 perfect pulley. 



We have given in the following cut a profile of the 

 sternum of the golden eagle, as about the average of 

 the order, and we add the humerus, to show the 

 relative size of that bone, as well as the enlarged pro- 



