On the ordinary view of each species having been independently created, we gain no scientific explanation.

Species of the same genus would occasionally exhibit reversions to lost ancestral characters.

Why is thought being a secretion of brain, more wonderful than gravity a property of matter? It is our arrogance, our admiration of ourselves.

In the eyes of most naturalists, the structure of the embryo is even more important for classification than that of the adult. For the embryo is the animal in its less modified state; and in so far it reveals the structure of its progenitor.

Embryology will reveal to us the structure, in some degree obscured, of the prototypes of each great class.

We cannot fathom the marvelous complexity of an organic being; but on the hypothesis here advanced this complexity is much increased. Each living creature must be looked at as a microcosm--a little universe, formed of a host of self-propagating organisms, inconceivably minute and as numerous as the stars in heaven.