On an average the
atavists may give lower hereditary figures, but the difference will be
only slight.
Such tricotylous double races offer highly interesting material for
inquiries into questions of heredity, as they have such a wide range of
variability. There is little danger in asserting that they go upwards to
nearly 100%, and downwards to 0%, diverging symmetrically on both sides
of their average (50-55%). These limits they obviously cannot
transgress, and are not even able to reach them. Samples of seed
consisting only of tricotyls are very rare, and when they are met with
the presumption is that they are too few to betray the rare aberrants
they might otherwise contain. Experimental evidence can only be reached
by the culture of a succeeding generation, and this always discloses the
hidden qualities, showing that the double [422] type was only
temporarily lost, but bound to return as soon as new trials are made.
This wide range of variability between definite limits is coupled with a
high degree of sensibility and adequateness to the most diverging
experiments. Our tricotylous double races are perhaps more sensitive to
selection than any other variety, and equally dependent on outer
circumstances. Here, however, I will limit myself to a discussion of the
former point.
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