No creature can possess such gemmules unless it inherits them from its parents, grandparents, or its less remote ancestors.

Now, the Jews are remarkably scrupulous as to marriage, and rarely contract such a union with individuals not of their own race.

This practice has gone on for thousands of years, and similarly also for thousands of years the rite of circumcision has been unfailingly and carefully performed.

If then the hypothesis of pangenesis is well founded, that rite ought to be now absolutely or nearly superfluous from the necessarily continuous absence of certain gemmules through so many centuries and so many generations.

Yet it is not at all so, and this fact seems to amount almost to an experimental demonstration that the hypothesis of pangenesis is an insufficient explanation of individual evolution.
Two exceedingly good criticisms of Mr.Darwin's hypothesis have appeared.
One of these is by Mr.G.H.