be placed, what was its character, when did the law of embryologic development begin to operate upon its descendants? Until some facts can be adduced which will have a satisfactory tendency to show the kinship of one animal with another by reason of ancestral descent from a common ancestral stock that was unlike either of them, the phenomena of embryologic development have no tendency to displace the hypothesis of special creations; for, on the latter hypothesis, the phenomena of resemblances and differences in the growth from the germ into the fœtus and from the fœtus into the newly born infant, evinced by any range of comparison of the different species, would be the same. If man was a special creation, and one of the higher quadrumana was also a distinct and separate creation, the establishment for each of a like process of procreation and gestation would produce all the resemblances of fœtal growth that obtain between them, and the ordained differences of their animal destinies would explain all the divergences. Let us see if this is not a rational conclusion. It is exceedingly difficult for the common reader of such a work as that of Mr. Spencer, on which I am now commenting, to avoid the influence of the perpetual assertion that facts are explicable upon one hypothesis alone. At each step in the argument, the array of facts terminates with the assertion that, upon the hypothesis of design, the facts are inexplicable; and yet we are furnished with no reasoning that has a tendency to show that the facts necessarily exclude the hypothesis of design, or, in other words, that the facts are inconsistent with that hypothesis. It is essential to understand what is the true scope of the hypothesis of special creation; for, without a definite idea of what that term implies, we have no proper means of comparing the facts of animal resemblances or differences with the rationality of the hypothesis that they resulted from an intentional design. Recollecting, then, that we are now pursuing the resemblances and divergences that are found in a comparison of the embryologic development of different species of animals, let us endeavor to understand the meaning of what I have suggested at the close of the last preceding paragraph; namely, the establishment for a large class of animals of a like general system of procreation and gestation, and the ordination of different destinies for the different species of animals belonging to that class. I have said that the two branches of this hypothesis would account for the resemblances in the embryological growth of different animals, and would explain the divergences which obtain among their embryological developments. The first inquiry is, whether this hypothesis presents a true philosophic idea of special creation. The next inquiry is, whether it affords a satisfactory explanation of the phenomena of comparative embryologic development.