Page:Popular Science Monthly Volume 33.djvu/806

786 highly developed, and the other atrophying, according to sex. This fact, of course, points back conclusively to primitive ancestors of fishes, reptiles, birds, and mammals, which were hermaphrodite. The argument for design is utterly put out of court by the awkwardness of the whole plan, and the disease and suffering caused in mammalian females by the ovaries having no



original connection with the uterus and by the survival of useless rudimentary organs. As a blind effort of Nature in the process of converting a hermaphrodite worm into a warm blooded mammal, the process has its wonderful and admirable side. The third set of kidneys are, of course, the permanent ones.

Prof. Cope, in his "Origin of the Fittest," draws attention to what he names the "law of acceleration and retardation." This law, though it may indirectly lead to the "survival of the fittest," is equally likely, through its blind action, to lead to the extinction of an animal which had once been the "fittest" in its