It is a false notion, and contrary to nature, that this passion in a woman is a derogation to her sex. The science of physiology indicates most clearly its propriety and dignity. There are wives who plume themselves on their repugnance or their distaste for their conjugal obligations. They speak of their coldness and of the calmness of their senses, as if these were not defects. Excepting those afflicted with vices of conformation, or with disorders of sensibility,--which amount to the same thing,--all wives are called upon to receive and pay the imposts of love; and those who can withdraw themselves from the operation of this mysterious law without suffering and with satisfaction, show themselves by that fact to be incomplete in their organization, and deficient in the special function of their being. There should be no passion for one which is not shared by both. Generation is a duty. The feeling which excites to the preservation of the species is as proper as that which induces the preservation of the individual. Passionate, exclusive, and durable love for a particular individual of the opposite sex, it has been well said, is characteristic of the human race, and is a mark of distinction from other animals. The instinct of reproduction in mankind is thus joined to an affectionate sentiment, which adds to its sweetness and prolongs infinitely its duration. Many physiologists have assigned to the feelings an important _rôle_ in conception, the possibility of which has even been doubted if there be no passion on the side of the woman. Although this extreme view is not tenable in the light of modern research, yet all recent authorities agree that conception is more assured when the two individuals who co-operate in it participate at the same time in the transports of which it is the fruit. It is also without doubt true that the disposition of the woman at that time has much power in the formation of the fœtus, both in modifying its physical constitution and in determining the character and temperament of its mind. The influence, long ago attributed by Shakspeare to 'a dull, stale, tired bed' in creating a 'tribe of fops,' is not a mere poet's fancy. In this manner also may be explained the results of prolonged continence upon the offspring, for desires are usually vivid in proportion to the previous period of rest. The father of Montaigne, returning after an absence of thirty-two years, during which he was engaged in the wars of Italy, begot his son, so justly celebrated in French literature. The father of J. J. Rousseau, after a considerable absence in Constantinople, brought to his wife the reward of a long fidelity.