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Vries, Hugo de, 1848-1935

"Species and Varieties, Their Origin by Mutation"

I have repeated it with the sugar-corn, which gives far better
material for demonstration. It starts from the inference that if
dissimilarity among the pollen grains is excluded, the diversity of the
ovules must at once became manifest and vice versa. In other terms, if a
hybrid of the first generation is not allowed to fertilize itself, but
is pollinated by one of its parents, the result will be in accordance
with the Mendelian formula.
In order to see an effect on the spikes produced in this way, it is of
course necessary to fertilize them with the pollen of the variety, and
not with that of the specific type. The latter would give partly pure
starchy grains and partly hybrid kernels, but these would assume the
same type. But if we pollinate the hybrid with pollen of a pure
sugar-corn, we may predict the result as follows.
If the spike of the hybrid contains dormant paternal marks in one-half
of its flowers and in the other half maternal latent qualities, the
sugar-corn pollen will combine with one-half of the ovules to give
hybrids, and with the other half so as to give pure sugar-grains. Hence
we see that it will be possible to count out directly the two groups of
ovules on inspecting the ripe and dry spikes. Experience teaches us
[298] that both are present, and in nearly equal numbers; one-half of
the grains remaining smooth, and the other half becoming wrinkled.


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