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Updated: May 8, 2025
The development of such a mode of reproduction by "Natural Selection" seems not less inexplicable than does its continued performance through the aid of "pangenesis." For how can gemmules attach themselves to others to which they do not normally or generally succeed?
Moreover, these gemmules are supposed to tend to aggregate themselves, and to reproduce in certain definite relations to other gemmules. Thus, when the foot of an eft is cut off, its reproduction is explained by Mr.
Hence they cannot reproduce the part in offspring. This explanation by no means implies that mutilation would usually affect the offspring. On the contrary, in all ordinary cases of mutilation the purely atavistic elements or gemmules would be set free from any modifying influence of the non-existent or mutilated part.
To this category belong Darwin’s gemmules, Haeckel’s plastidules, Nägeli’s micellæ, Weismann’s labyrinth of ids, determinants, and biophors within the germ-plasm, and Roux’s ingenious hypothesis of the struggle of parts, which is an attempt to apply the Darwinian principle within the organism in order here also to rebut the teleological interpretation by giving a scientific one. Heredity.
Turning to the organic world, even on the hypothesis of Mr. Herbert Spencer or that of Mr. Darwin, it is impossible to escape the conception of innate internal forces. With regard to the physiological units of the former, Mr. Spencer himself, as we have seen, distinctly attributes to them "an innate tendency" to evolve the parent form from which they sprang. With regard to the gemmules of Mr.
Darwin's keen analogy of the fertilization of plants by pollen renders development from without conceivable, but as there are no insects to convey gemmules to their destination, each kind of gemmule would have to be exceedingly numerous and easily attracted from amongst an inconceivable number of other gemmules.
As to formations without the requisite gemmules. Mr. Lewes and Professor Delpino. Difficulty as to developmental force of gemmules. As to their spontaneous fission. Pangenesis and Vitalism. Paradoxical reality. Pangenesis scarcely superior to anterior hypotheses. Buffon. Owen. Herbert Spencer. "Gemmules" as mysterious as "physiological units." Conclusion.
The hypothesis in question may be stated as follows: That each living organism is ultimately made up of an almost infinite number of minute particles, or organic atoms, termed "gemmules," each of which has the power of reproducing its kind.
Darwin also does not see the force of the objection to the power of self-division which must be asserted of the gemmules themselves if Pangenesis be true. The objection, however, appears to many to be formidable. To admit the power of spontaneous division and multiplication in such rudimentary structures, seems a complete contradiction.
Darwin will be the first to admit that though a creature have no reproductive system, in any ordinary sense of the word, yet every unit or cell of its body may throw off gemmules which may be free to move over every part of the whole organism, and which "natural selection" might in time cause to stray into food which had been sufficiently prepared in the stomachs of the neuter bees.
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