242 ARTICULATIONS OF THE VERTEBRA. 



with the intervertebral matter, and narrower about the middle 

 of each of the bodies of the vertebrae. It appears to consist of 

 longitudinal tendinous fibres, which are similar to those of the 

 anterior ligament. The fibres of which these ligaments are 

 composed, are more closely connected by origin and insertion 

 with the intervertebral matter, than with the bodies of the 

 vertebrae. Some of the fibres are inserted into the next verte- 

 brae or intervertebral substance below their place of origin, 

 others into the second or third, and some into the fourth or 

 fifth. 



The oblique processes of the vertebrae are covered with 

 cartilage, and are invested with a synovial membrane, like the 

 other movable articulations. In the neck and back these 

 membranes are thin and delicate ; but in the loins they are 

 blended with ligamentous fibres which give them additional 

 strength. 



Some of the most curious and interesting ligaments of the 

 spine, or indeed of the body, are those which are attached to 

 the bony plates or arches that extend from the oblique to the 

 spinous processes of each vertebrae. These plates form a great 

 portion of the posterior part of the vertebral canal and the 

 vacant spaces between them are filled up by these ligaments, 

 which extend from the plates of each upper vertebra of those 

 of the next vertebra below. 



They are situated between the spinal process and the oblique 

 processes on each side. 



They are, therefore, two distinct ligaments between the two 

 vertebrae, one on each side of the spinal process ; and as they 

 extend only from the plates or arches of one vertebra to those 

 of the other, they must necessarily be very short. They are 

 much more conspicuous on the internal surface of the vertebral 

 cavity than they are externally. They are thick and substantial, 

 and very elastic ; their color resembles that of a yellowish 

 adeps ; and from that circumstance they are called the yelloiv 

 or elastic ligaments. They complete the cavity for the spinal 

 marrow. There are twenty-three pairs in all. 



As the plates or arches to which they are connected must 



