278 H;. WALTER RANSON 



PLATE 3 



EXPLANATION OF FIGURES 



6 Lissauer's tract and entering dorsal root in the first sacral segment. Letter- 

 ing is the same as in figure 5, which gives the topography of the high power drawing. 

 Non-meduUated fibers are separating out along the borders of the entering radicle 

 and along the connective tissue septa which separate it into fascicles. At d non- 

 medullated fibers are seen running forward into Lissauer's tract. X 100. 



7 Same area as represented in figure 6 but about 50 ^ farther cephalad. Letter- 

 ing the same as in figures 5 and 6. The non-meduUated fibers of the dorsal root, 

 which have separated out along the connective tissue septum c, are seen running 

 forward into the tract of Lissauer, a. X 100. 



8 Lissauer's tract and entering dorsal root in the fifth lumbar segment. For to- 

 pography see figure 4. At a, b, c, is seen a part of an encircling band of pi a which 

 surrounds and constricts the entering radicle. U^pon the surface of this band a 

 layer of non-medullatetl fibers is seen entering the cord. At d, and e, are seen thin 

 layers of non-medullated fibers at the jjeriphery of the radicle and along the sep- 

 tum separating the radicle into two fascicles. X 100. 



