Essays in scientific synthesis / by Eugenio Rignano.

  • Eugenio Rignano
Date:
[1918]
Catalogue details

Licence: In copyright

Credit: Essays in scientific synthesis / by Eugenio Rignano. Source: Wellcome Collection.

    59/264 page 55
    The action to which the process of development is due irradiates from a special zone of the embryonic organism called the central zone of development, constituted by the germinal substance. This formative action is due to the successive modes of being of the system of distribution or circulation of trophic nervous energy, constituted by all the nuclear excitations or discharges simultaneously active in the different cells of the embryo. These nuclear discharges meet along the intercellular protoplasmic bridges, compositions and decompositions of the respective currents taking place in turns ; the resulting system of nervous circulation thus penetrates the whole organism at each stage of its development, and at each moment gives rise to its complex morphologico-physiological state. The germinal substance contained in the nucleus of the fertilized egg consists of a large number of “ specific potential elements ” ; that is to say, of a large number of elementary accumulators of nervous energy, each of which is capable, as they are discharged, of giving rise, not to a generic activation of this nervous energy, as electric accumulators do for electric energy, but to the activation of one and only one specific mode of being of this nervous energy. These specific potential elements activate successively, one after another, from the beginning to the last term of the development. Every nervous current, every nervous excitation, whether it is directly derived from a single nucleus or from the composition or decomposition of several nuclear currents or excitations, on subsequently cross¬ ing any other nucleus whatever of the soma, deposits
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