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Butler, Samuel, 1835-1902

"Essays on Life, Art and Science"

The issue, therefore, is important, and is being
fiercely contested by those who have invested their all of
reputation for discernment in Charles-Darwinian securities.
Professor Weismann's theory is, that at every new birth a part of
the substance which proceeds from parents and which goes to form the
new embryo is not used up in forming the new animal, but remains
apart to generate the germ-cells--or perhaps I should say "germ-
plasm"--which the new animal itself will in due course issue.
Contrasting the generally received view with his own, Professor
Weismann says that according to the first of these "the organism
produces germ-cells afresh again and again, and that it produces
them entirely from its own substance." While by the second "the
germ-cells are no longer looked upon as the product of the parent's
body, at least as far as their essential part--the specific germ-
plasm--is concerned; they are rather considered as something which
is to be placed in contrast with the tout ensemble of the cells
which make up the parent's body, and the germ-cells of succeeding
generations stand in a similar relation to one another as a series
of generations of unicellular organisms arising by a continued
process of cell-division." {30}
On another page he writes:-
"I believe that heredity depends upon the fact that a small portion
of the effective substance of the germ, the germ-plasm, remains
unchanged during the development of the ovum into an organism, and
that this part of the germ-plasm serves as a foundation from which
the germ-cells of the new organism are produced.


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