Thus I suppose, as almost every one else, so far as I can gather, supposes, that we are descended from ancestors of widely different characters to our own. If we could see some of our forefathers a million years back, we should find them unlike anything we could call man; if we were to go back fifty million years, we should find them, it may be, fishes pure and simple, breathing through gills, and unable to exist for many minutes in air. It is admitted on all hands that there is more or less analogy between the embryological development of the individual, and the various phases or conditions of life through which his forefathers have passed. I suppose, then, that the fish of fifty million years back and the man of to-day are one single living being, in the same sense, or very nearly so, as the octogenarian is one single living being with the infant from which he has grown; and that the fish has lived himself into manhood, not as we live out our little life, living, and living, and living till we die, but living by pulsations, so to speak; living so far, and after a certain time going into a new body, and throwing off the old; making his body much as we make anything that we want, and have often made already, that is to say, as nearly as may be in the same way as he made it last time; also that he is as unable as we ourselves are, to make what he wants without going through the usual processes with which he is familiar, even though there may be other better ways of doing the same thing, which might not be far to seek, if the creature thought them better, and had not got so accustomed to such and such a method, that he would only be baffled and put out by any attempt to teach him otherwise. And this oneness of personality between ourselves and our supposed fishlike ancestors of many millions of years ago, must hold also between each individual one of us and the single pair of fishes from which we are each (on the present momentary hypothesis) descended; and it must also hold between such pair of fishes and all their descendants besides man, it may be some of them birds, and others fishes; all these descendants, whether human or otherwise, being but the way in which the creature (which was a pair of fishes when we first took it in hand though it was a hundred thousand other things as well, and had been all manner of other things before any part of it became fishlike) continues to exist—its manner, in fact, of growing. As the manner in which the human body grows is by the continued birth and death, in our single lifetime, of many generations of cells which we know nothing about, but say that we have had only one hand or foot all our lives, when we have really had many, one after another; so this huge compound creature, LIFE, probably thinks itself but one single animal whose component cells, as it may imagine, grow, and it may be waste and repair, but do not die.