Nevertheless all living things have much in common, in their chemical composition, their cellular structure, their laws of growth, and their liability to injurious influences.
We see this even in so trifling a fact as that the same poison often similarly affects plants and animals; or that the poison secreted by the gall-fly produces monstrous growths on the wild rose or oak-tree.
With all organic beings, excepting perhaps some of the very lowest, sexual reproduction seems to be essentially similar.
With all, as far as is at present known, the germinal vesicle is the same; so that all organisms start from a common origin.