ON NEURONOGENESIS 347 



and muscle, respectively the truth of which statements 

 is at once negatively obvious in the pathological con- 

 ditions known as to mention only two, " glossy skin," 

 and "myopathy." Hence, the formidable, but altogether 

 reasonable, conclusions, must be drawn, that the external 

 endowment of the human body known to science, art, 

 and poetry, as the skin, and those structures so much 

 loved, and fondly developed, by the athlete, as the 

 muscles, are alike the products of silent neural growth 

 and circulation ; and, therefore that a consistent, and 

 reasonable, search after, and cultivation of, them, on lines 

 thus dictated, cannot, and will not, be disappointed, 

 because founded on the unalterable basis of cause and 

 effect, of physiological nutrition, growth and development. 

 Thus a proper nutritive supply, in quantity and quality, 

 a continued maintenance of the patency of the circulating 

 ways through which the formative plasma must pass, and 

 a proper assimilative reception of that plasma by the 

 cutaneous, and muscular, structures involved, must of 

 physiological necessity be followed by altogether un- 

 objectionable results being due to the operation of 

 normal laws, and conditions while, at the same time, 

 it cannot be wondered at that the stiffening, and 

 blanching, effects, of time, lead to whitening, and de- 

 nudation, of dermal appendages, wrinkling of the once 

 smooth skin, and shrinking of the once packed, and 

 resistant, muscles. 



Besides our arteries we have, therefore, to reckon with 

 the neural vasculature, and with the incidents of neural 

 change, in the estimation of the process of " aging," and 

 the progress of senility. In ministering to the nutrition 

 of the systemic nervature in all its parts, and jointly with 

 the sympathetic nervature, in sustaining the nutrition of 

 the dermal, and musculo-skeletal structures, the neuroglial 

 matrix may be said to resemble the blood in its nutritional 

 relationship to the non-nervous structures, so called, of 

 the body generally, thus from them are taken up, re- 

 spectively, the nutritive plasma of the sympathetically 

 innervated structures, and organs, and the systemically 

 innervated textures, neuronal, dermal, and musculo- 

 skeletal. The recognition of these facts is sufficient to 



