EIGHTEENTH CENTURY EVOLUTIONISTS. 245 



processes of nature in the production of animals and the conservation 

 of them.' The general processes which Maupertuis thought it espe- 

 cially important that zoological science should investigate are those 

 through which animal individuals and species have come to have the 

 differences of form and function that distinguish them. Maupertuis, 

 in a word, appears to have clearly envisaged the genetic problem in 

 biolog}', at a period in the history of thought when genetic problems 

 generally were little considered. The center of interest in zoology 

 therefore lay, for him, in the problems of embryogeny and of heredity. 

 Although not himself an anatomist, he made himself familiar with 

 investigations made by others on the minute anatomy of the embryo. 

 And, as I have intimated, he never tired of insisting that the facts of 

 heredity should be investigated, in the case of animals, by experiments 

 in the interbreeding of species and varieties, and, in the case of human 

 beings, by a collation of family histories. 



The opinions of Maupertuis on these matters are expressed chiefly 

 in the work called 'Venus Physique' (1745) and in the 'Systeme de la 

 Nature' (1751). The latter first appeared in the form of a Latin 

 dissertation ostensibly delivered at Erlangen by one Dr. Baumann. 

 Maupertuis found it expedient thus to shelter himself against reproach 

 on account of any heterodox tendencies that the book might be found 

 to contain. Four editions — all but the first in French — were called for 

 within four years, and the author soon assumed responsibility for his 

 work. In the 'Venus Physique' Maupertuis essayed the popular style, 

 and the book is consequently marred by passages written in an abomin- 

 ably rhetorical and affected manner. But, none the less, it constitutes, 

 if I am not mistaken, the first important attack made in the eighteenth 

 century upon the theory of the preformation of the embryo. Harvey 

 had advanced the doctrine of epigenesis nearly a century earlier, but 

 his arguments had failed to convince his successors, and his observa- 

 tions upon the chick had been shown by Malpighi to be partially 

 erroneous.* At the time when Maupertuis wrote, preformationism had 

 long been the ruling doctrine in embryology; an immense weight of 

 scientific authority was in its favor. Among the philosophers Male- 

 branche and Leibniz had argued for it, among the great physiologists 

 and anatomists Swammerdam, Eedi, Malpighi, Leeuwenhoek, Winslow 

 and Haller had taught it. Bonnet was yet to give it its most elaborate 

 exposition and defense; and three quarters of a century later it was 

 still to find an adherent in Cuvier. The 'Venus Physique' is a review 

 of the preformation theory in its several forms, designed to show that 

 the evidence against it is conclusive. 



Of the arguments for epigenesis which Maupertuis offers it is not 

 possible, in this brief paper, to give any sufficient account. He relies 

 in part upon the observations of Harvey — and in so doing shows himself 



* ' De formatione pulli in ovo,' 1673; ' De ovo incubato,' 1686. 



