fix’d and unchangeable; our single Natures being sufficient to preserve the human Race, in a successive Series, and their double one being no more; which alone was the Purpose of such Formations in all animal Beings, and no other. But no such Restraints attend larger Animals, and therefore no such Nature is at all necessary in them; however, tho’ all others are limited to certain Seasons, as to their generative Capacities, it is very strange that no Appearance has ever been had of two Sexes in any one upon Dissection, (though many have been supposed of a double Nature) but the human; who have no limits set to their Powers of procreating, and who on all accounts seem to have the least need of any thing of the Kind. If it be objected that it happens not to human Nature through any Necessity, but only from a Lusus of Nature; I answer, that no such Lusus can happen, and it will be very evident, if we only reflect a little upon the Nature of Generation, which will be more amply treated of in another Place; however, one Principle will be sufficient to our Purpose here, which is, that the Rudiments or Parts of all Animals whatsoever are already form’d in the Ovum[27], and that nothing can be produced by the Males, but a Juice capable of giving Motion, Explication, and Extension to those Parts, and that since we know the common Standard of Nature in human Bodies is, that there should be but one Sex in one Body, it is impossible that there should be the least Imperfection in the Rudiments of any one of the Ova, since they were implanted in Females from the Beginning of Time, by the Almighty _Fiat_, and were under the Restriction of that Law, that every Day’s Experience confirms to us is certain; for if there was not so absolute a Law, with respect to the being of only one Sex in one Body, we might then, indeed, expect to find every Day many preposterous Digressions from our present Standard. That there are certain Limits set to the Things of Generation appears no where better than when Animals of different Species meet and copulate; the Animal that is the Product of such a Congress is in no wise capable of producing an Off-spring like itself, to this there is an absolute _ne plus ultra_, and why? Because, indeed, if such were capable of Generation, we should, by degrees, have a new set of Heterogenous Animals upon Earth. But it is plain, it never was the Design of the Almighty, since every Species of Animals are the same now that they ever were, and we must, from this Argument, expect no other while time subsists. And indeed, were we to have regard to the Notions of some of the Ancients concerning Generation, as, that the Male and Female Semina meeting form’d a Child of either Sex, according to the Predominance of the Strength or Quantity of either Semen, and if both were equal in Quantity and Quality, a Child of both Sexes was begotten, I say, were we to have regard to this, we might still