Strong hereditary dispositions of character may be recognized in early infancy. When the ancestry of a man is well known the roots of his recent phylogeny may be traced to his ancestors. Here we observe the effect of crossing between varieties or different races, or on the contrary that of consanguinity. This effect is observed in character and in sexual disposition, as much as in the shape of the nose, or the color of the skin and hair, etc. It is important that men should learn to know themselves, and also study each other from this point of view before marrying. On the whole, we may say that the average civilized man of our race possesses as his "phylogenetic baggage" a strong sexual appetite, very variable sentiments of love, generally somewhat mediocre, (we have seen that conjugal love is more strongly developed in most monkeys than in man), lastly altruistic or social sentiments which are still deplorably weak. The latter, no doubt, form no part of the sexual life, but they must be taken into consideration for they are its most important derivatives, and it is indispensable for our modern social life to develop them in harmony with family and conjugal love. Hereditary instincts can easily be observed in children. When one of them is good, it gives evidence at an early age of the sentiments of sympathy or altruism, such as pity and affection, as well as an instinctive sentiment of duty, the object of which is not yet social. All these sentiments are at first only applied to human individuals known to the child, domestic animals, or even inanimate objects. On the other hand, the ant, from the beginning of its existence, shows an inherited instinct or sentiment of complete social duty. In man, social sentiments properly so-called, have to be acquired by education, but they require for their expansion a considerable degree of inherited sentiments of sympathy and duty. A person without morals can easily acquire social phraseology but not social sentiment. A few more points require to be considered.