356 BIOLOGICAL PHYSICS 



The systemic nervous system, moreover, represents a 

 nutrition effector, inasmuch, as by its cell processes, it 

 takes up from the neuroglial amorphous elements, the 

 pabulum for its own cell growth, and axonal extensions. 



Along the fibro-axonal extensions of every nerve cell, 

 this neuronal nutritive pabulum is passed from the cell, by 

 regular circulation, or growth, to the various textures in 

 which the nerve terminals, afferent, and efferent, are 

 histologically distributed, and with which they become 

 histologically continuous. The nutritive process here 

 indicated reaches, therefore, by continuity, every texture 

 histologically related to the systemic nervous system, 

 along a neuro-vasculature, the lumen of which is patent 

 enough to allow circulation of axis-cylinder substance, and 

 medullary substance, respectively, materials, which traverse 

 their respective containing membranes, along every axonal 

 process, and which ultimately reach the periphery of the 

 systemic nervous system, and become structurally incor- 

 porated by the textures in which they terminate, or continue 

 farther circulating by continuous histological succession, 

 until these facilities become exhausted, when they are, 

 necessarily, finally arrested, or shed, or returned into the 

 blood stream. All these nutritive phenomena require for 

 their accomplishment, the existence of circulatory facilities, 

 and these facilities, we contend, are to be found in every 

 axonal fibre, with its histological continuations, where - 

 ever they lead to these fibres and their continuations being 

 patent, and pervious, to the passage of the nutritive 

 materials taken up by the nerve cells, and their contained 

 nuclei, hence the skin, on the afferent side of the nervous 

 peripheral extensions, and the muscles, with their attached 

 tendons, intervening periosteum, and bones, on the efferent 

 side of the nervous peripheral extensions, respectively, 

 represent the structures to which the nutritive neuronal 

 material is conveyed, as nutritive pabulum, or excretional 

 material. 



This nutritive role, which we have assigned to the 

 systemic nervous system, embraces a large proportion of 

 the nutritive work of the body, at least it embraces the 

 nutrition of the whole structures subserving the functional 

 work of the central, or systemic, nervous system, with the 



