Before I had finished writing this book I fell in with Professor Mivart’s “Genesis of Species,” and for the first time understood the distinction between the Lamarckian and Charles-Darwinian systems of evolution. This had not, so far as I then knew, been as yet made clear to us by any of our more prominent writers upon the subject of descent with modification; the distinction was unknown to the general public, and indeed is only now beginning to be widely understood. While reading Mr. Mivart’s book, however, I became aware that I was being faced by two facts, each incontrovertible, but each, if its leading exponents were to be trusted, incompatible with the other. On the one hand there was descent; we could not read Mr. Darwin’s books and doubt that all, both animals and plants, were descended from a common source. On the other, there was design; we could not read Paley and refuse to admit that design, intelligence, adaptation of means to ends, must have had a large share in the development of the life we saw around us; it seemed indisputable that the minds and bodies of all living beings must have come to be what they are through a wise ordering and administering of their estates. We could not, therefore, dispense either with descent or with design, and yet it seemed impossible to keep both, for those who offered us descent stuck to it that we could have no design, and those, again, who spoke so wisely and so well about design would not for a moment hear of descent with modification. Each, moreover, had a strong case. Who could reflect upon rudimentary organs, and grant Paley the kind of design that alone would content him? And yet who could examine the foot or the eye, and grant Mr. Darwin his denial of forethought and plan? For that Mr. Darwin did deny skill and contrivance in connection with the greatly preponderating part of organic developments cannot be and is not now disputed. In the first chapter of “Evolution Old and New” I brought forward passages to show how completely he and his followers deny design, but will here quote one of the latest of the many that have appeared to the same effect since “Evolution Old and New” was published; it is by Mr. Romanes, and runs as follows:— “It is the _very essence_ of the Darwinian hypothesis that it only seeks to explain the _apparently_ purposive variations, or variations of an adaptive kind.” {17a}