THE COURSE OF THE FIBEES IN THE SPINAL COKD. 



353 



irregularly spotted. Behind, toward the lumbar region, the pyramids separate into 

 their anterior and lateral tracts. In the latter there degenerate also many bundles 

 of greater or less length, which belong to the association-systems connecting different 

 levels of the cord. Usually the shorter fibers lie nearer the gray matter, while the 

 longer ones are farther away. Naturally these association-tracts are degenerated 

 most of all at points immediately above and below the place of compression; 

 farther away in either direction one finds only a few, and those are the longest. 

 In the posterior columns just lateral to GoU's column there pass downward for a 



Fig. 227. — Schema of cross-section of spinal cord, in which the central course 

 of some important bundles is indicated. Compare with it the non-schematic Fig. 

 223, right. The axis-cylinders from the ventral horn-cells to the posterior root 

 are omitted. Tracts of the first order shown by dark lines, those of the second 

 order, by dotted lines. For translation of German tei-ms see explanation accom- 

 panying Fig. 223. 



distance the descending fibers from those root-bundles which are affected by the 

 compression. They form a, comma-shaped tract, — Schultze's comma, — which lies in 

 not always the same position, according to the particular, interrupted root. This 

 tract, whose relationship to the dorsal roots is still disputed, was traced by Hoche a 

 distance of more than eight vertebras before it disappeared in the gray matter. 



Still another small deposit of fibers, lying on the dorsal side of the posterior 



