LAMARCK THE ZOOLOGIST 



189 



"Radiaires" included the Echinoderms (the Vers 

 echinoderms of Bruguifere) and the Medusae (his Ra- 

 diaires molasses"), the latter forming the Discophora 

 and Siphonophora of present zoologists. This is an an- 

 ticipation of the division by Leuckart in 1 839 of the Ra- 

 diata of Cuvier into Coelenterata and Echinodermata. 



The " Polypes " of Lamarck included not only the 

 forms now known as such, but also the Rotifera and 

 Protozoa, though, as we shall see, he afterwards in his 

 course of 1807 eliminated from this heterogeneous 

 assemblage the Infusoria. 



Comparing this classification with that of Cuvier * 

 published in 1798, we find that in the most important 

 respects, i.e., the foundation of the classes of Crusta- 

 cea, Arachnida, and Radiata, there is a great advance 

 over'Cuvier's system. In Cuvier's work the molluscs 

 are separated from the worms, and they are divided 

 into three groups, Cephalopodes, Gasteropodes, and 

 Acephales — an arrangement which still holds, that of 

 Lamarck into Mollusques c6phal6s and Mollusques 

 ac6phalds being much less natural. With the elimi- 

 nation of the MoUusca, Cuvier allowed the Vers or 

 Vermes of Linn6 to remain undisturbed, except that 

 the Zoophytes, the equivalent of Lamarck's Polypes, 

 are separately treated. 



He agrees with Cuvier in placing the molluscs at 

 the head of the invertebrates, a course still pursued 

 by some zoologists at the present day. He states in 

 the Philosophie Zoologique \ that in his course of lec- 



* Tableau iUmentaire de VHistoire naturelle des Animaux. Paris, 

 An VI. (1798). 8vo, pp. 710. With 14 plates, 

 f Tome i., p. 123. 



