Page:George Archdall Reid 1896 The present evolution of man.djvu/137

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ORGANIC EVOLUTION—THE FACTORS
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He founds this opinion on some researches by the latter gentleman, which tend to show that cell-division is not absolute, but that cells are connected by "a fine protoplasmic reticulum, so that the alleged independence of the reproductive cells does not exist" (p. 41). Now as regards some cells, for instance nerve cells, it has long been known that they are connected by a fine protoplasmic reticulum, but until Mr. Sedgwick did it, it had never occurred to any one to call the brain for instance "a continuous mass of vacuolated protoplasm."

Nevertheless, let us concede the point, and agree, for the sake of argument, to regard a multicellular organism, e.g. an elephant, as a continuous mass of vacuolated protoplasm—as a sort of gigantic unicellular organism. How does the concession help Mr. Sedgwick? Does it aid him in proving, for example, that if changes are acquired in that part of the vacuolated mass which we call the elephant's trunk, that these changes will so affect that part of the vacuolated mass which we call the germ cell, that when the latter has developed into another elephant, there will spontaneously appear in the trunk of the descendant animal variations similar to those which were acquired by the parent—variations which arose in the parent in response to stimulation, and which arise anew in the offspring only in response to similar stimulation?

Mr. Sedgwick writes, and Mr. Spencer quotes—

"Finally, if the protoplasm of the body is primitively a syncytium, and the ovum until maturity a part of the syncytium, the separation of the generative products does not differ essentially from the internal generation of a Protozoon, and the inheritance by the offspring of peculiarities first appearing in the parent, though not explained, is rendered less mysterious; for the protoplasm of the whole body being continuous, change in the molecular constitution of any part of it would