It was entirely natural to primitive man that in the spring the trees and plants should bud and send forth leaves and blossoms, to be followed later by fruit, "each after its kind." This, also, had always occurred from his earliest recollection and that of his elders, and it occasioned no thought upon his part. It was only when floods, drouths and other calamities interfered with this orderly sequence of events that any mystery was presented or any thought required. It is clear that among these common and natural occurrences, which were simply accepted without question because they had always happened, must be classed the bringing forth of young by all mammals. Man had always observed that the females of all the animals about him brought forth young, "each after its kind." This was to be expected and gave him no surprise, nor, in the then condition of his intellect, did it give rise to a thought as to its cause. Likewise, his own womankind gave birth to young, from time to time, just as did the other animals, and there was no cause for speculation or thought in regard to this; the occurrence was too common to be a mystery. There being then no knowledge of fatherhood, there were no fathers, and for many generations no relatives were known except in the female line. Consequently, there was no family hearthstone; no paternal love; no marriage. The relations of the sexes was purely physical and were generally indiscriminate, as opportunity might afford; but doubtless, with some, this companionship was continued for a longer or shorter period, as circumstances or congeniality might induce.