GHAR EE Rx Vi 
THE STEPS IN THE DEVELOPMENT OF LAMARCK’S 
VIEWS ON EVOLUTION BEFORE THE PUBLICA- 
TION OF HIS © PATLOSOPATE , Z00LOGIOCEL. 
I. From the Systime des Animaux sans Vertcbres(1801). 
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 
Systeme des Animaux sans Vertcbres, this being the 
first sketch or prodromus of his later great work on 
the, invertebrate. "animals, “Inthe pretace of tiis 
book, referring to the openine: lecture; inevsaysi:: “ol 
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- 
* Discours @’ ouverture du Cours de Zoologie donné dans le Muséum 
national a’ fistoire naturelle, le 2% floréal,an8 de la République (1800). 
Floréal is the name adopted by the National Convention for the 
eighth month of the year. In the years of the Republic 1 to 7 it ex- 
tended from April 20 to May 1g inclusive, and in the years 8 to 13 
from April 21 to May 20 (Century Cyclopedia of Names). Vhe lecture, 
then, in which Lamarck first presented his views was delivered on 
some day between April 21 and May 20, 1800. 
