THE BONES OP THE BODY. 303 



thus serve the important purpose of increasing the size.oi 

 the head without adding to its weight. 



THE BONES OF THE BODY. 



The neck is formed by seven bones, which, with the ex 

 ception of the two first, are very much alike. The first is 

 connected with the occipital, or bone of the skull, with 

 ■which it forms a joint possessing much motion in a vertical 

 direction. In the human subject it is termed the atlas, from 

 its supporting the head. It forms a joint behind with the 

 dentata, as the second bone is termed, from its having in the 

 front part a process like a tooth, which, however, aflbrds the 

 head considerable lateral motion. All the bones of the neck 

 are extremely irregular in shape ; they all possess a large 

 hole through the centre for the passage of the spinal marrow, 

 and small ones at the sides for the exit of nerves and arte- 

 ries. They have also projections on each side and above 

 for the attachment of inuscles, and each one forms a joint 

 both before and behind which afibrds that great flexibility 

 to the neck which most animals possess. 



The hack or chine is composed ol separate bones called 

 vertebrae, of which there are thirteen belonging to the back 

 alone. They all possess, like those of the neck, a hole 

 through the centre for the passage of the spinal cord, as well 

 as a small one at the side for the exit of the nerves. The 

 superior projections or processes are much higher than those 

 of the neck, but considerably shorter than we find in the 

 horse ; and thus we have high withers in this animal and 

 low ones in the sheep, and they are also shorter in the im- 

 proved breeds than in the wilder races of sheep, a channel 

 between the shoulders and along the ' back being justly re- 

 garded as a sign of a disposition to fatten. These processes 

 serve for the attachment of muscles, as well as of a strong 

 elastic substance' which is attached to all the bones of the 

 neck as well as to the occiput, and serves to support the 

 head, and thus relieves the muscles to a great extent. 



The ribs are attached to the vertebrae by means of a joint 

 — one rib is joined to two vertebrae, and vice versa, thus af 

 fording the ribs a certain extent of motion. There are thir- 

 teen ribs on each side, eight true and five false ; the former 

 are attached to the sternum or breast-boiie, and the latter are 

 merely joined to the former at their lower parts, vifhich is 

 formed of cartilage. The ribs should spring from the back 



