The portrait of Malpighi shown in Fig. 62 is taken from his life by Atti. From descriptions of his personal appearance (see page 58) one would think that this is probably a better likeness than the strikingly handsome portrait painted by Tabor, and presented by Malpighi to the Royal Society of London. For a reproduction of the latter see page 59. Malpighi's Rank.--On the whole, Malpighi should rank above Harvey as an embryologist, on account of his discoveries and fuller representation, by drawings and descriptions, of the process of development. As Sir Michael Foster has said: "The first adequate description of the long series of changes by which, as they melt the one into the other, like dissolving views, the little white opaque spot in the egg is transformed into the feathered, living, active bird, was given by Malpighi. And where he left it, so for the most part the matter remained until even the present century. For this reason we may speak of him as the founder of embryology." The Period of Wolff Between Harvey and Wolff, embryology had become dominated by the theory that the embryo exists already pre-formed within the egg, and, as a result of the rise of this new doctrine, the publications of Wolff had a different setting from that of any of his predecessors. It is only fair to say that to this circumstance is owing, in large part, the prominence of his name in connection with the theory of epigenesis. As we have already seen, Harvey, more than a century before the publications of Wolff, had clearly taught that development is a process of gradual becoming. Nevertheless, Wolff's work, as opposed to the new theory, was very important. While the facts fail to support the contention that he was the founder of epigenesis, it is to be remembered that he has claims in other directions to rank as the foremost student of embryology prior to Von Baer. As a preliminary to discussing Wolff's position, we should bring under consideration the doctrine of pre-formation and encasement.