CHAPTER XVI 



THE STEPS IN THE DEVELOPMENT OF LAMARCK'S 

 VIEWS ON EVOLUTION BEFORE THE PUBLICA- 

 TION OF HIS PHILOSOPHIE ZOOLOGIQUE 



I. From the Systime des Animaux sans Vertibres{\%oi). 



The first occasion on which, so far as his published 

 writings show, Lamarck expressed his evolutional 

 views was in the opening lecture * of his course on 

 the invertebrate animals delivered in the spring of 

 1800, and published in 1801 as a preface to his 

 Systbme des Animaux sans Vertibres, this being the 

 first sketch or prodromus of his later great work on 

 the invertebrate animals. In the preface of this 

 book, referring to the opening lecture, he says : " I 

 have glanced at some important and philosophic 

 views that the nature and limits of this work do not)! 

 permit me to develop, but which I propose to take 

 up elsewhere with the details necessary to show on 

 . what facts they are based, and with certain explana- 



* Discoiirs d''ouverture du Cours de Zoologie donni dans le Mushun 

 national d^ Histoire natureUe^ le '2.\ jlpr^al^ an& de la j^/publiqiie {1%0<S). 

 Floreal is the name adopted by the National Convention for the 

 eighth month of the year. In the years of the Republic I to 7 it ex- 

 tended from April 20 to May 19 inclusive, and in the years 8 to 13 

 from April 21 to May 20 {Century Cyclopedia of Names). The lecture, 

 then, in which Lamarck first presented his views was delivered on 

 (Some day between April 21 and May 20, 1800. -^ 



