The hereditary transmission of disease, or of a tendency to it, has of late attracted more attention than it formerly did, and medical literature has been enriched by many able and learned disquisitions on the subject. Its importance seems to be generally appreciated, to a certain extent, but not to so great an extent, as a more perfect knowledge of its operation, and the vastness of its influence, would justify. From Burton's ’Anatomy of Melancholy’ may be quoted many passages by ancient writers, showing a lively appreciation of the fact of hereditary transmission, especially of disease. Fernelius says, “Such as the temperature of the father is, such is the son's, and, look, what disease the father had when he begot him, his son will have after him, and is as well the inheritor of his infirmities as of his lands.” “And where the complexion and constitution of the father is corrupt, then,” saith Roger Bacon, “the complexion and constitution of the son must needs be corrupt, and so the corruption is derived from the father to the son.” Burton also quotes passages from Hippocrates, Buxtorfius, Lemnius, Paracelsus, Crato, Bruno Seidelius, Daniel Sennertus, Forestus, Rodericus a Fonseca, Lodovicus Mercatus, and many others, referring to hereditary transmission, or the transmission of melancholy. The last mentioned wrote a book on the subject, ‘De Morbis Hereditariis,’ and therein first notices what is now called atavism. “It skips, in some families, the father and goes to the son, or takes every other, and sometimes every third, in a lineal descent, and doth not always produce the same, but some like, and a symbolising disease.” This last remark is of importance, as anticipating a fundamental principle in modern investigations into the subject. Burton himself highly estimates the importance and power of hereditary transmission, when he says, “These secondary causes, hence derived, are commonly so powerful that (as Wolphius holds) they do often alter the primary causes and decrees of the heavens.” This most learned and far-seeing author mentions facts, and hints at conclusions which are only now being understood and arrived at, and shows that an appreciation of the truth of hereditary transmission had formed the basis of laws forbidding the marriage between persons in any whit allied, and of those stern and implacable decrees, which, among certain Indian tribes, and even in Scotland, at an early period, necessitated the destruction of those that suffered from madness, gout, falling sickness, or any such dangerous diseases.