112 NORMAL HISTOLOGY. 



b. Non-medullated Nerve-fibres. 



These are also called fibres of Remak. Unlike 

 the nerve-fibres which we have just been studying, 

 they possess no medullary sheath and no neuri- 

 lemma. They are simply grayish translucent cords 

 of varying diameter ; they are indistinctly longitu- 

 dinally striated, and are intimately connected with 

 one another by frequent inosculations. The fibres 

 seem to divide and send off oblique branches to join 

 neighboring fibres. Flattened, elongated nuclei lie 

 at frequent intervals upon the surface of the fibres. 

 These fibres considerably resemble, in their general 

 appearance, the fibrillated fibres of ordinary connec- 

 tive tissue, but careful examination shows them to 

 be entirely distinct structures. 



They are grouped in bundles to form nerves, 

 sometimes alone, but very frequently in connection 

 with medullated nerve-fibres. Thus, in the pneumo- 

 gastric, we find a considerable part of the fibres to 

 be non-medullated, and intimately bound in, by the 

 intra-fascicular connective tissue, with medullated 

 fibres. The non-medullated fibres originate in 

 nerve-cells of a peculiar structure, to be presently 

 described ; but of their peripheral terminations we 

 know almost nothing. 



II. NERVE-CELLS. 



Nerve-cells, or ganglion-cells, as they are frequently 

 called, although presenting the greatest diversity in 

 form, have yet some quite distinctive characters in 



