Now it is claimed that for the occurrence of this kind of modification in conjunction with homology only one rational explanation is possible, and that explanation is evolution. If this contention be a sound one, and Dorlodot, who claims certitude for the evolutionary solution, insists that it is such, then, in the name of sheer logical consistency, but one course lies open to us. We cannot stop at Wasmann’s comma,[4] we must press on to the very end of the evolutionary sentence and sing with the choristers of Woods Hole: [4] Rev. Erich Wasmann, S. J., accepts the evolutionary inference from homology as regards _plants_ and _animals_. When it comes to _man_, however, he attempts to draw the line, and argues painstakingly against the assumption of a bestial origin of the human body. “It’s a long way from Amphioxus, It’s a long way to us; It’s a long way from Amphioxus, To the meanest human cuss. Good-bye fins and gill slits; Welcome skin and hair. It’s a long, long way from Amphioxus, But we came from there.” In this predicament it will not do, as we shall see presently, to adopt Mr. McCann’s expedient of balancing anatomical differences against anatomical resemblances. To do so is to court certain and ignominious defeat. We must, therefore, examine the argument dispassionately. If it be solid, we must accept it and give it general application. If it be unsound, we must detect its flaws and expose them. Intellectual honesty allows us no alternative! Moreover, in weighing the argument from organic homology we must not lose sight of the two important considerations previously stressed: (1) that the inference of common ancestry in the case of homologous forms is based, not upon this or that particular likeness, but upon an entire group of coördinated resemblances; (2) that the resemblances involved are not exterior similarities, but deep-seated structural uniformities perfectly compatible with diversities of a superficial and functional character. “Nothing,” says Dr. W. W. Keen, “could be more unlike externally than the flipper of a whale and the arm of a man. Yet you find in the flipper the shoulderblade, humerus, radius, ulna, and a hand with the bones of four fingers masked in a mitten of skin.” (_Science_, June 9, 1922, p. 605.)