which its surface has passed. Not only did Madame Clémence Royer initiate us into transformism. In her masterly introduction she went still further. Carrying the exposition to its final consequences, she provoked a useful revolution in the ideas then current. She dared to say what many men of science would only have left to be inferred. Her translation, revealing the name of Darwin to the French public, who hardly knew of it at that period, gave the occasion for a very active conflict between the partisans of "creationism" and the Nantese philosophy. The success of this work was so great as to induce her to complete her preface by publishing a few years afterward a work wholly her own, _Origine de l'Homme et des Sociétés_ (Origin of Man and Societies, 1870), which, being her best production, deserves a special analysis. With the assistance of documents collected by the most famous anthropologists, Madame Royer reconstitutes the history of the primitive ages of mankind, and after studying its origins and development she seeks for the bonds that connect the great human family with the rest of living Nature; and finally forecasts its future from its past. In the first part she takes up the question of the origin of life and of its transformations upon the earth. The living species are grouped around man, who is the topmost shoot of the gigantic "tree of life." Two laws regulate the transmission of life--the law of heredity and the law of variability. The former assures the continuation of the type, and the latter variety in its modifications. The organic kingdom as a whole oscillates between these two contrary rules which fix limits each upon the other and which suffice to explain the successive appearance through the ages of different forms of life. The organic individual is thus the solution of a problem in algebra set to Nature. Atavism is the constant quantity, and the force of variation is the perpetually changing unknown factor. The problem is therefore complex, but the principles to which the variable is subject resolve themselves into a series of partial laws which are deduced from an aggregate of observations, and which, according to our author, one may summarize as he goes. Most of the variations reveal themselves in the embryo during the fætal period. But after its birth the young product is affected not only by the ambient medium, but also by the consequences of the reproductive act. The latter, in fact, having impressed the initial movement upon its organism, reacts incessantly against the modifying influences of the ambient, and atavism prevails as always the resultant unless important accidents come in to change the course.