The fact is that neither of these plants being indigenous, they are not perfectly adapted for fertilisation by British insects.
fertilisation marks the striking of the death-blow to all that went before.
An examination of the grasses will show at once that they are adapted for fertilisation by the wind.
The Snapdragon is especially adapted for fertilisation by Humble Bees.
See Darwin's fertilisation of Orchids for the many extraordinary and complex arrangements in these plants.
Such differences will, of course, be introduced at the time of fertilisation.
Taking frogs' eggs immediately after fertilisation, I compressed them strongly between parallel, horizontally placed glass plates.
There was further, as we may suppose, a gain in certainty of fertilisation.
I have already alluded to the various ways in which flowers are adapted to fertilisation by insects.
Thus his original interest in the fertilisation of flowers was evolutionary.