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THE HUMAN BODY. 



through the cord, supporting the nervous elements; some of 

 the coarser of these are represented at 6, 7, and elsewhere in 

 Fig. 84, but from these still finer processes arise, as represented 

 at d and e in Fig. 85. The ultimate finest tissue directly 

 supporting the nervous elements directly, is the neuroglia. 

 In the white columns, the cord (Fig. 85) will be seen to be 



/IG. 84. A thin transverse section of half of the spinal cord magnified about 

 10 diameters. 1, anterior fissure ; 2, posterior fissure ; 3. canalis central is ; 8, pia 

 mater enveloping the cord ; 6, 7, bands of pia mater penetrating the cord and sup- 



gorting its nerve elements ; 9, a posterior root ; 10, bundles of an anterior root ; a, 

 , c, d, e, groups of nerve cells in the gray matter. 



mainly made up of medullated nerve-fibres which run longi- 

 tudinally and therefore appear in the transverse section as 

 circles, with a dot in the centre, which is the axis cylinder. 

 At b in Fig. 85 these fibres are represented, the intermediate 

 connective tissue being omitted, while at e this latter alone is 

 represented in order to show more clearly its arrangement. 

 At the levels of the nerve-roots horizontal white fibres are 

 found (9 and 10, Fig. 84, and ,.Fig. 85), running into the 

 gray matter, and others exist at the bottom of the anterior 

 fissure, running from one side of the cord to the other. In 



