LAMARCK THE ZOOLOGIST 195 



supposed he would, from its superficial resemblance 

 to polyps, have placed it among the polyps. To 

 Lamarck we are also indebted for the establishment 

 in 1 81 8 of the molluscan group of Heteropoda. 



Lamarck's acuteness is also shown in the fact that, 

 whereas Cuvier placed them among the acephalous 

 molluscs, he did not regard the ascidians as molluscs 

 at all, but places them in a class by themselves 

 under the name of Tunicata, following the Sipunculus 

 worms. Yet he allowed them to remain near the 

 Holothurians (then including Sipunculus) in his 

 group of Radiaires echinodermes, between the latter 

 and the Vers. He differs from Cuvier in regard- 

 ing the tunic as the homologue of the shell of Lamelli- 

 branches, remarking that it differs in being muscular 

 and contractile. 



Lamarck's fame as a zoologist rests chiefly on this 

 great work. It elicited the highest praise from his 

 contemporaries. Besides containing the innovations 

 made in the classification of the animal kingdom, 

 which he had published in previous works, it was a 

 summary of all which was then known of the in- 

 vertebrate classes, thus forming a most convenient 

 hand-book, since it mentioned all the known genera 

 and all the known species except those of the insects, 

 of which only the types are mentioned. It passed 

 through two editions, and still is not without value 

 to the working systematist? 



In his Histoire des Progres des Sciences naturelles 

 Cuvier does it justice. Referring to the earlier volume, 

 he states that " it has extended immensely the knowl- 

 edge, especially by a new distribution, of the shelled 



