To begin with, there is no act of pairing, no coitus, but the male discharges a number of conical or bell-shaped “spermatophores,” each of which is crowned by a bunch of spermatozoa, the male germs necessary to ensure fertilization of the ova. These spermatophores adhere to the bottom of the stream, and are gathered up by the female, either directly, by placing herself in such a position that they can be seized by the lips of the genital opening, or by seizing the spermatophore, with its fertilizing germs, between her hind legs and pressing it home! The more one contemplates this extraordinary proceeding the more one marvels at the evolution of a departure from the normal sexual relations so inconceivably strange. Here one sees the purpose of the aphrodisiac in its true light. But for these facts it would have seemed certain that its primary object was to enable the male to relieve desire and at the same time to accomplish its end—the fertilization of ova—without undue waste. And this, in all the cases so far discussed, is possible only when the female has become inflamed with a like desire for coitus. But here the male finds relief, without more ado, by depositing the precious germs upon the ground. The display then is indeed to serve as an aphrodisiac. For the continuation of the race now rests entirely on the female. Any defect in the orderly working of her sexual appetite means the waste of the spermatozoa and the failure to effect fertilization. We cannot suppose that there is any realization of these facts, or any deliberate action on her part, but rather that she derives pleasurable feelings from the necessary passage of the spermatophore, which, probably, she recognizes by its smell.