144 COMPAKISONS OF STllUCTURE IN ANIMALS. 



tebr£B are ossified together, consolidated iuto 

 one, tlioiigh each preserves its distinctness of 

 outUne, and little splints of bone derived froui 

 the transverse processes overlap each other, 

 and thus add to the strength of this portion of 

 the vertebral column. It is rigid and un- 

 yielding. To this part the true ribs are 

 attached, bending thence round to the breast- 

 bone, on the margin of which they are in- 

 serted. But even the ribs have to be strength- 

 ened, and this is effected by a broad flat 

 process, projecting from the posterior margin 

 of each rib : at the central part of the arch it 

 forms, and prolonged backwards and upwards 

 so as to overlap the next rib in succession. Li 

 some birds these processes are more bold and 

 decided than in others. 



When Ave pass from the dorsal vertebrae, we 

 find the lumbar and sacral vertebrae unitina; 

 with the hip or haunch-bones, to form one 

 large solid portion, every part being con- 

 solidated together. Now if Ave consider the 

 backward position of the legs, and of the hip- 

 joint, and reflect that these limbs thus dis- 

 adA^antageously placed, inasmuch as the bird is 

 uot balanced upon them, have to sustain on 

 the ground the weight of the,body, Ave shall 



