8 Veterinary Elements. 



some very light bones which are of importance in their 

 relation to the act of breathing. These bones are cov- 

 ered with a very delicate mucous membrane, containing 

 a great number of small blood vessels, the air as it passes 

 over this membrane becomes warmed before being taken 

 in by the lungs. The teeth, although properly classed 

 with the bones of the head, will be treated of when the 

 digestive system is being taken up. 



The Neck. Behind and below the head we find the 

 spinal (vertebral) column, made up of a number of sec- 

 tions, each called a vertabrae. These vertebrae have a 

 hollow passage (spinal canal) through their centers, this 

 canal houses the spinal cord, thus protecting it against 

 injury. These vertebrae are so constructed as to allow 

 of movements between them, varying in degree accord- 

 ing to their location. Considerable motion is necessary 

 and is provided for between the vertebras of the neck, 

 such enables the head and neck to be placed in different 

 positions. The acts of raising and lowering, turning 

 sidewise are accomplished by the action of powerful 

 muscles attached to these bony sections. The site of the 

 junction of the bones of the head and neck is the region 

 of the poll, and it is these bones that are sometimes 

 affected in severe cases of Poll Evil. The bony sections 

 in the neck (cervical) region, number seven, and are 

 somewhat alike, the two first (atlas and axis) showing 

 the more marked differences. 



The Back. Passing along the back (dorsal region) we 

 find that the vertebrae forming this region are shorter 

 and more numerous, being 18 to 19 in number. They 

 resemble the bones of the neck, save that their upper 



