ABSTRACT
For in truth fertilization is a far more archaic phenomenon than the temporary union of male and female in the sex act. We have seen, in fact, that the development of genitality and of its executive organ has its earliest inception in the amphibians, but propagation by fertilization, on the other hand, in the lowest unicellular organisms, in the amoeba. The mode of adjustment to the earlier catastrophe—namely, fertilization-may indeed have served as a prototype, and may have contributed towards the fusion into a single entity of the originally independent impulses to fertilization and to coitus. The unpleasurable character of the tension discharged in fertilization would be the ultimate cause, as already stated, of the uniting of the genital with the organs of excretion. Among unicellular organisms there are transitional forms which stand midway between conjugating and non-conjugating types, as the amphibians between water- and land-inhabiting forms.
