EXTRACT XXVIII. A. 



ON THE GROWTH OF THE SYSTEMIC NERVE CELL, 

 AND WHAT FOLLOWS. WITH NEURO-PSYCHIC 

 GENESIS. 



ON studying the subject of Eczema, and allied affections, 

 we were led to infer, that the epidermic scales, and the 

 cells from which they were evolved, must, to some extent, 

 have been composed of the "cast off" material, or 

 apparel, of the afferent peripheral terminal nerve (Fig. 128) 

 structures, and that they, thus, represent an excretory 

 product; in other words, the continuous "shedding" of 

 the skin must represent, to some, indeed the larger, 

 extent, the detachment, from the outer surface of the 

 organism, of effete material, derived from the growth 

 outwards to the skin of the neuroglial matter, through the 

 nerve cell, as the medullary, and nuclear, or axis cylinder, 

 protoplasm, of the various neurons, along the axonal 

 nerve fibres, until it reaches the various peripheral nerve 

 endings, throughout the entire cutaneous envelope. A 

 similar idea had struck us before, in connection with the 

 study of rheumatism, and the manner of termination of 

 the efferent or motor nerve fibrils in the substance of 

 the muscles. 



We would add, besides, that the secretory role, which 

 we here have assigned to the nerve cell, in all its varieties, 

 necessitates the existence, or provision, of an excretory 

 mechanism, equal to the discharge of the secreted material, 

 and that, in looking, and searching, for such a mechanism, 

 we have followed the axonal processes of these cells, to 

 their synapses, their ganglionic cell interruptions, and 



