The nervous system and its conservation . have already hinted, the neuron theory isunder a fire of criticism. We must take pains to suggestpossible departures from the doctrine which may cometo be established in time. It has been said before thatcontinuity of protoplasm from neuron to neuron isassumed by many. The view that a synapse is a bridge 3 34 THK XKKVOUS AXU ITS < \SKRVATI<JN rather than a place of contact impairs the suppo-edindividuality of the units. A more important changein our conceptions may have to he adopted if the observa-tions of certain student- are confirmed.
The nervous system and its conservation . have already hinted, the neuron theory isunder a fire of criticism. We must take pains to suggestpossible departures from the doctrine which may cometo be established in time. It has been said before thatcontinuity of protoplasm from neuron to neuron isassumed by many. The view that a synapse is a bridge 3 34 THK XKKVOUS AXU ITS < \SKRVATI<JN rather than a place of contact impairs the suppo-edindividuality of the units. A more important changein our conceptions may have to he adopted if the observa-tions of certain student- are confirmed. The statement that the axon of a nerve-fiber maycontain a number of fibrils, perhaps to be regarded asindependent carriers of impulses, will be recalled. Itis claimed that in some cases fibrils like these are to bedemonstrated within the perikarya and extending outinto the dendrites. The suggestion has, therefore, beenmade that everything else in the nervous system is sub-ordinate in importance to a continuous network, slender. Fig. 7.—To illustrate the conception of the neuropile whichsubordinates the cells of the nervous system to a continuous net-work of fibrils sometimes within and sometimes without the cellboundaries. and intricate. This it is proposed to call the m nro/>il<.A synapse, in the light of this interpretation, is merelythe place where fibrils pass from the sphere of influenceof one perikaryon to that of another (Fig. 7). The chief result of 1he<e recent discoveries will probablybe to lessen the prominence given to the perikarya indescriptions of nervous activity and to emphasi/e the partplayed by the fibrillar conductors. One interesting func-tion of the perikarya remains undisputed. This is theresponsibility for the maintenance of normal nutritionthrough all the processes of the neuron. No matter howfar an axon may stretch from the cell-body to which it MINUTE STRUCTURE OF THE NERVOUS TISSUES 35 belongs, its most distant portion is yet dependent up
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Keywords: ., bookau, bookcentury1900, bookdecade1910, booksubjectnervoussystem
