12 Foster Physical Basis of Psychical Events. 



nutrition. Scattered amidst the living, fully-elaborated 

 substance of the cell, in which substance, and in which 

 substance alone, often apparently structureless, the living 

 powers seem to reside, we are able to detect granules and 

 heaps of granules of varying refractive power and varying 

 reaction towards colouring and other chemical reagents. 

 These we have reason to think are either food material 

 about to undergo further elaboration, or waste material 

 about to be further transformed and ejected. These 

 appreciable granules whose changes we can see, and many 

 other things which we cannot see and never shall see, are 

 tokens of the laboratory; they are signs of t*he nutritive 

 work which is going on. 



Now, in the nerve unit, the neurone, while we have like 

 abundant evidence, like conspicuous laboratory tokens of 

 nutritive labours in that part of the cell which surrounds 

 the nucleus, in what has been called the perikaryon, as 

 well as in the ordinary dendrites, all such tokens are 

 strikingly scanty if not entirely absent in the axon which 

 constitutes an efferent fibre, or the modified dendrite which 

 constitutes an afferent fibre. Indeed, while staining chro- 

 mophile granules, or groups of granules, small or large, 

 supply conspicuous features of the perikaryon of every 

 nerve cell as well as of the dendrites to even a long distance 

 from the nucleus, the axon, the axis cylinder process of 

 the cell is distinguished almost as soon as it separates off 

 from the perikaryon (or from the dendrite in the cases 

 where it seems to start from a dendrite) by the paucity or 

 even absence of such granules. In the perikaryon and in 

 the greater part of the dendrite, the elaborated, active, 

 truly nervous material is crowded and elbowed by the 

 grosser material out of which it is making itself, in the 

 axon as little as possible of this grosser material is left, 

 the greater part of the axon is sifted, elaborated matter 

 clogged as little as possible by coarser lower stuff 



