waste of words that it
seems better to quote the translation of the passage as given by
Professor Bateson, [Footnote 18] than to attempt to explain it in
other words. Mendel says:--

[Footnote 18: Bateson: _Mendel's Principles of Heredity_.
Cambridge. The University Press. 1902.]

The results of the previously described experiments induced further
experiments, the results of which appear fitted to afford some
conclusions as regards the composition of the egg and pollen-cells
of hybrids. An important matter for consideration is afforded in
peas (_pisum_) by the circumstance that among the progeny of the
hybrids constant forms appear, and that this occurs, too, in all
combinations of the associated characters. So far as experience
goes, we find it in every {215} case confirmed that constant progeny
can only be formed when the egg-cells and the fertilizing pollen are
of like character, so that both are provided with the material for
creating quite similar individuals, as is the case with the normal
fertilization of pure species.

We must therefore regard it as essential that exactly similar
factors are at work also in the production of the constant forms in
the hybrid plants. Since the various constant forms are produced in
one plant, or even in one flower of a plant, the conclusion appears
logical that in the ovaries of the hybrids there are formed as many
sorts of egg-cells and in the anthers as many sorts of pollen-cells
as there are possible constant combination forms, and that these egg
and pollen-cells agree in their internal composition with those of
the separate forms.

In point of fact, it is possible to demonstrate theoretically that
this hypothesis would fully suffice to account for the development
of the hybrids in the separate generations, if we might at the same
time assume that the various kinds of egg and pollen-cells were
formed in the hybrids on the average in equal numbers.

Bateson says in a note on this passage that this last and the
preceding paragraph contain the essence of the Mendelian principles of
heredity. Mendel himself, after stating this hypothesis, gives the
details of a series of experiments by which he was able to decide that
the theoretic considerations suggested were founded in the nature of
plants and their germinal cells.

It will, of course, be interesting to realize what the bearing of
Mendel's discoveries is on the