io8 



THE NERVOUS SYSTEM 



In the anterior funiculus, in addition to the fasciculus proprius which imme- 

 diately surrounds the gray matter, there is a thin layer of similar fibers spread 

 out along the border of the anterior fissure and known as the sulcomarginal 

 fasciculus. This tract also contains the fibers which descend into the cord from 

 the medial longitudinal bundle of the medulla oblongata. 



As a general rule the short fibers of the fasciculus proprius lie nearer the 

 gray substance than the fibers of greater length; and the long tracts, which 



Fasciculus gracilis .., 



Spinocerebellar, spinotectal, and lateral^ 

 spinothalnmic tracts 



Fasciculus inter fascicular is 



Septomarginal fasciculus- 

 Lateral corticospinal tract* 



Septomarginal fasciculus, oval area of Flechsig , 

 Lateral corticospinal tract* 



Cervical enlargement 

 ascending degeneration 



Upper thoracic 

 ascending degeneration 



Middle thoracic 

 site of compression 



Lower thoracic 

 descending degeneration 



Upper lumbar 

 descending degeneration 



Lower lumbar 

 descending degeneration 



Fig. 76. Ascending and descending degeneration resulting from a compression of the thoracic 

 spinal cord in man. Marchi method. (Hoche.) 



connect the spinal cord with the brain, occupy the most peripheral position. 

 But the fact must not be overlooked that many fibers of the fasciculus proprius 

 are intermingled with those of the long tracts. 



LONG DESCENDING TRACTS OF THE SPINAL CORD 



Fibers which arise from cells in various parts of the brain descend into the 

 spinal cord, where they form several well-defined tracts. The most important 



