The value of the principle of atavism in off-setting degeneracy is nowhere better illustrated than in the history of famous families of degenerates like those of the Binswangers, of "Margaret," of the Jukes, as well as those reported in France, Germany, Austria, Russia, and the Scandinavian countries. The Rougon-Macquart family of Zola (which had its actual prototype in the Kerangal family described by Aubry[107]) had, like these, several scions in whom former normality regained its power through atavism. Sometimes this atavism is not shown to any greater extent than a slight modification of the abnormality or morbidity. Telegony, the so-called and much-debated heredity of influence, whereby the children of a second marriage resemble the first husband, may be explained by a biologic principle demonstrable in the lower animals, whereby conjugation not sufficient to fecundate ova is sufficient so to impress them that when finally fecundated they bear characteristics of the first conjugation. Its part in either normal or degenerate heredity is but slight. Some instances charged to it might be attributed to mental impression on the mother. Luys[108] excellently sums up the whole question of heredity when he remarks: "Heredity governs all the phenomena of degeneracy with the same results and the same energy as it controls moral and physical resemblances in the offspring. The individual who comes into the world is not an isolated being separated from his kindred. He is one link in a long chain which is unrolled by time, and of which the first links are lost in the past. He is bound to those who follow him, and to the atavic influences which he possesses; he serves for their temporary resting-place, and he transmits them to his descendants. If he come from a race well endowed and well formed, he possesses the characters of organisation which his ancestors have given him. He is ready for the combat of life, and to pursue his way by his own virtues and energies. But inversely, if he spring from a stock which is already marked with an hereditary blemish, and in which the development of the nervous system is incomplete, he comes into existence with a badly balanced organisation; and his natural defects, existing as germs, and in a measure latent, are ready to be developed when some accidental cause arises to start them into activity." CHAPTER IV CONSANGUINEOUS AND NEUROTIC INTERMARRIAGE