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STUDENTS HISTOLOGY 



FIG. 152. DIAGRAM OF THE RELATIONS OF THE CELLS AND FIBERS OF THE SPINAL 

 CORD. (BAKER, AFTER LENHOSSEK.) 



The right side shows the cells of different classes found in the cord, and their processes. The 

 left side gives the processes of cells whose bodies are either beyond the cord or at other levels, 

 with the distribution of their collaterals. 



a, a. Motor cells of the anterior horn. 



c. Commisstiral cells. 



d. Golgi commissural cell. 



e. e. Columnar cells of antero-lateral column. 



f. f. Columnar cells of posterior column. 



g. Golgi cell of posterior horn. 



1. Fibers of posterior root forming the antero-posterior reflex tract. 



2. Fibers passing to the column of Clarke. 



3. Commissural fibers of posterior root. 



4. Fibers that enter the posterior horn, 

 k, k. Collaterals of antero-posterior column. 



1, 1. Collaterals from the pyramidal tracts. 



columns. Commissural cells give off axis-cylinder processes to the 

 opposite side of the cord, by way of the anterior gray commissure. 

 The axis -cylinders of some ganglion -cells terminate in the gray 

 matter itself. The fibers of the posterior nerve-roots, arising from 

 the cells of the spinal ganglia, divide into ascending and descend- 

 ing branches, which enter the posterior columns. 



The difficulties in the way of tracing the paths of the fibers 

 in the cord are enhanced by the numerous collaterals arising 

 from many axis -cylinders. 





