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58 with the right leg crossed on the left. One of his daughters had the same habit from birth; she constantly assumed that position in the cradle, notwithstanding the resistance offered by the swaddling-bands. The same author assures us that he has oftentimes noticed in children other habits no less extraordinary, which they must have received from their parents, and which cannot be attributed either to imitation or to education. Darwin gives another instance: A child had the odd habit of setting its fingers in rapid motion whenever it was particularly pleased with any thing. When greatly excited, the same child would raise the hands on both sides as high as the eyes, with the fingers in rapid motion, as before. Even in old age he experienced a difficulty in refraining from these gestures. He had eight children, one of whom, a little girl, when four years of age, used to set her fingers going and to lift up her hands after the manner of her father. Finally, heredity has been observed in handwriting. There are families in which the special use of the left hand is hereditary. Various peculiarities of sensorial conditions are transmitted in a similar way. Nearly all the members of the Montmorency family were affected with an incomplete strabismus, which used to be called the Montmorency look. The incapacity to distinguish between different colors is notoriously hereditary. The distinguished English chemist, Dalton, and two of his brothers, were thus affected, and hence the affection itself received the name of Daltonism. Deafness and blindness are sometimes hereditary, though not often, and deaf-muteness still more rarely. Some curious instances are given of the transmission of certain perverse tastes. Lucas, according to Zimmermann, relates the following: A man in Scotland was possessed of an irresistible desire of eating human flesh. He had a daughter. Although removed away from her father and mother, who were sent to the stake before she was one year old, and although brought up among respectable people, this girl, like her father, succumbed before her strange craving for human flesh. This is clearly a case allied to insanity.

Insanity is, beyond all doubt, transmitted by heredity. Among 1,375 lunatics Esquirol found 337 cases of hereditary transmission. Guislain and other physicians, on a rough estimate, represent the patients affected with hereditary insanity as one-fourth of the total number of the insane. Moreau, of Tours, and others, hold that the proportion of the former is still greater. The heredity of insanity does not imply merely direct transmission of insanity (alienation), properly so called; hysteria, epilepsy, chorea, idiocy, hypochondria, may result from insanity, and, vice versa, they may produce insanity. In passing from one generation to another, these various neuroses (nervous affections) are in some way transformed into one another. Herpin,of