Page:Popular Science Monthly Volume 4.djvu/66

56 and physiological functions which constitute the species. At all events, it is plain that in this case the parents are completely and absolutely repeated in the children. Were this not so, there would be no species, but only successions of beings without any relations between them save that of generation. Within the historic limits of experience, the continuous reproduction of specific characters, always identical, or, in other words, the permanent integrity of species, is a fact almost beyond question. The distinctive characters of races and of varieties are transmitted with less regularity and fixity, and it is precisely on the various transformations that these may undergo from one generation to another that a famous school of naturalists rest when they would prove, in a more or less extended sense, the transformation of organisms in time. But more irregular still and more variable is the repetition of those characters which, as being less general than those of a species or a race, may be regarded as belonging to the individual. Thus, in proportion as the characters become more particular and more special, the more are they released from the law of heredity, and the greater is the probability that the children will differ from the parents. Still, observation––an observation as ancient as the human race itself––shows that these characters, though personal, may be transmitted by generation. But within what limits, and under what conditions? This we have to inquire into with all circumspection, for there is no other subject in which one is so much in danger of making missteps, and of slipping on dangerous inclines.

Heredity is especially noticeable in the continuity of physiological and pathological conditions. It is very clearly evident in the expression and features of the physiognomy. This was observed by the ancients; hence the Romans had their Nasones, Labeones, Buccones, Capitones, etc. (Big-nosed, Thick-lipped, Swollen-cheeked, Big-headed). Of all the features, probably the nose is best preserved by heredity: the Bourbon nose is famous. Heredity also manifests itself by fecundity and longevity. In the old French noblesse there were several families which possessed high procreative vigor. Anne de Montmorency, who, at the age of over sixty-five years, could still, at the battle of St. Denis, smash with his sword the teeth of a Scotch soldier who was giving him the death-blow, was the father of twelve children. Three of his ancestors, Matthew I., Matthew II., and Matthew III., taken all together, had eighteen, and of these fifteen were boys. The son and grandson of the great Condé had nineteen between them, and their great-grandfather, who lost his life at Jarnac, had ten. The first four Guises reckoned in all forty-three children, of whom thirty were boys. Achille de Harley had nine children, his father ten, and his great-grandfather eighteen. In some families this fecundity endured through five or six generations. The average length of life depends on locality, diet, stage of civilization, but individual longevity appears