With reference to suicide, there is no fact that has been more clearly established than that of its hereditary character. Of all diseases to which the various organs are subject, there are none more generally transmitted from one generation to another than affections of the brain. It is not necessary that the disposition to suicide should manifest itself in every generation; it often passes over one, and appears in the next, like insanity unattended with this propensity. But if the members of the family so predisposed are carefully examined, it will be found that the various shades and gradations of the malady will be easily perceptible. Some are distinguished for their flightiness of manner, others for their strange eccentricity, likings and dislikings, irregularity of their passions, capricious and excitable temperament, hypochondriasis and melancholia. These are often but the minute shades and variations of an hereditary disposition to suicidal madness. A gentleman suddenly, and without any apparent reason, cut his throat. The father had always been a man of strong passions, easily roused, and when so, was extremely violent. The brother was a man of impulse; he always acted by fits and starts, and therefore never could be depended upon. The sister had a strange, unnatural, and superstitious horror of particular colours and odours. A yellow dress caused a feeling approaching to syncope, and the smell of hay produced great nervous excitement. The grandfather had been convicted of homicide, and had been confined for two years in a mad-house. Andral relates the case of a father who died from the effects of disease of the brain; the mother died sane. They had six children, three boys and three girls. Of the boys, the eldest was a man of original mind; the second was very extravagant in his habits, and was ultimately confined in a mad-house; the third was extremely violent in his temper. Of the girls, one had fits of apoplexy, and became insane; the other died at her accouchement, with symptoms of derangement; the third died of cholera, not, however, until she exhibited indications of mental aberration. A case more singular than the last is recorded. All the members of a particular family, being hereditarily disposed, exhibited, when they arrived at a certain age, a desire to commit self-destruction. It required no exciting cause to develope the fatal disposition. No wish was expressed, or attempt made, to overpower the suicidal inclination, and the greatest industry and ingenuity were exercised by the parties in order to effect their purpose. In two cases, the propensity was subdued by proper medical and moral treatment; but, just in proportion to its being suppressed, did the idea of suicide appear to fix itself resolutely in the mind. The desire came upon the individuals like the attacks of intermittent fever.