LECTURE III. Ill 



large and perpendicular stream, compress- 

 ing the bag into a small compass, and 

 forcing its sides into numerous wrinkles. 



Behind the body of each vertebra there 

 is a bony ring, and these rings, when op- 

 posed to one another, constitute a canal for 

 the protection and transmission of that 

 important part, the medulla spinalis. 

 From these rings, seven processes are con- 

 tinued, four of which serve to make joints, 

 connecting the vertebrae with one another. 

 There are two ascending and two descend- 

 ing articular processes. Two processes 

 also stand out laterally, and are called 

 transverse, and one backwards, which, be- 

 ing in general pointed, is named spinous. 

 These latter processes chiefly serve to give 

 attachment to the muscles which support 

 and move the vertebral column. 



Upon the form of the articular processes, 

 the degree and kind of motion which takes 

 place between the several vertebrae, seem 

 entirely to depend. In the neck, the op- 

 posing surfaces of the articular processes 



