Auch bei anderen Hybriden, deren Nachkommen sich ähnlich verhalten, dürfen wir eine gleiche Ursache voraussetzen; für jene hingegen, welche constant bleiben, scheint die Annahme zulässig, dass ihre Befruchtungszellen gleichartig sind und mit der Hybriden-Grundzelle übereinstimmen.
We can presuppose the same cause also in other hybrids whose descendants behave similarly; for those, however, which remain constant the assumption seems admissible that their fertilisation cells are of the same kind and correspond to the hybrid foundation cell.
Mendel is referring to his exploration of fertilisation in other plants than Pisum in Section 10 of his paper.
constant = constant See p. 5, s. 5.
fertilisation cells = Befruchtungszellen See p. 24, s. 3.
of the same kind = gleichartig See p. 41, s. 7.
foundation cell = Hybriden-Grundzelle Sherwood has “primordial cell of the hybrid”, Bateson “foundation-cell of the hybrid”, adding “fertilised ovum” in parenthesis. The manuscript actually has hybriden Grundzelle, that is, it uses hybrid as an adjective; see p. 10, s. 12 on the significance of this. Just like Befruchtungszelle, this seems to be a term that Mendel used idiosyncratically to designate the product of the fusion of a germ and a pollen cell. We could not find it in any of the cytological works Mendel is likely to have consulted (see p. 24, s. 3).