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apparently. The malformations, defects, or special characteristics may die out, or the course of trans- mission may be interrupted. The disease or peculiarity may not appear again for one or more generations; or it may be limited to certain lines of transmission, as through the males only, or through the females only, of the family; and in these again, according to certain restrictions. It is probably little known how much Harvey had thought upon this subject of hereditary trans- mission, and how very clearly and concisely he expresses his own views upon several matters which, under new names, are at this moment exciting the greatest attention. In reference to the subject of family likeness,' says Harvey, 'we may be permitted to inquire as to the reason why the offspring should at one time bear a stronger resemblance to the father, at another to the mother, and at a third to progenitors, both ma- ternal and paternal, further removed; particu- larly in cases where at one bout, and at the same moment, several ova are fecundated. And this, too, is a remarkable fact, that virtues and vices, marks and moles, and even particular dispositions to disease, are transmitted by parents to their
