“In any case,” as Professor Caullery tells us in his Harvard lecture on the “Problem of Evolution,” “we do not see in the facts emerging from Mendelism, how evolution, in the sense that morphology suggests, can have come about. And it comes to pass that some of the biologists of greatest authority in the study of Mendelian heredity are led, with regard to evolution, either to a more or less complete agnosticism, or to the expression of ideas quite opposed to those of the preceding generation; ideas which would almost take us back to creationism.” (Smithson. Inst. Rpt. for 1916, p. 334.) It is, of course, impossible within the limits of a single chapter to convey any adequate impression of all that Mendel’s epoch-making achievement portends, but what has been said is sufficient to give some idea of the acuteness of the crisis through which the theory of organic evolution is passing as a result of his discovery. In its classic forms of Lamarckism, Darwinism and De-Vriesianism, the survival of the theory is out of the question. Whether or not it can be rehabilitated in any form whatever is a matter open to doubt. Transfixed by the innumerable spears of modern objections, its extremity calls to mind the plight of the Lion of Lucerne. Possibly, it is destined to find a rescuer in some great genius of the future, but of one thing, at least, we may be perfectly certain, namely, that, even if rejuvenated, it will never again resume the lineaments traced by Charles Darwin. In the face of this certainty, it is almost pitiful to hear the die-hards of Darwinism bolstering up a lost cause with the wretched quibble that, though natural selection has been discredited as an explanation of the differentiation of species, Darwinism “in its essentials” survives intact. For, if there is any feature which, beyond all else, deserves to be called an essential of Darwin’s system, surely it is natural selection. For Darwin it was “the most important” agency of transformation (cf. “Origin of Species,” 6th ed., p. 5). Apart from his hypothesis of the summation through inheritance of slight variations (“fluctuations”), now completely demolished by the new science of genetics, it represented his sole contribution to the philosophy of transformism. It alone distinguishes Darwinism from Lamarckism, its prototype. Without it the “Origin of Species” would be Hamlet without the Prince of Denmark. With it Darwin’s fame should stand or fall. Therefore, since Darwin erred in making it “the most important means of modification,” Darwinism is dead, and no grief of mourners can resuscitate the corpse. “Through the last fifty years,” says Bateson, “this theme of the natural selection of favored races has been developed and expounded in writings innumerable. Favored races certainly can replace others. The argument is sound, but we are doubtful of its value. For us that debate stands adjourned. We go to Darwin for his incomparable collection of facts.