_Classification of Lamarck._ _Classification of Cuvier._ 1. Mollusca. I. _Mollusca._ 2. Crustacea. II. _Insectes et Vers._ 3. Arachnides (comprising 1. Insectes. the Myriapoda). 2. Vers. 4. Insectes. III. _Zoophytes._ 5. Vers. 1. Echinodermes. 2. Meduses, Animaux 6. Radiaires. infusorines, Rotifer, Vibrio, Volvox. 7. Polypes. 3. Zoophytes proprement dits. Of these, four were for the first time defined, and the others restricted. It will be noticed that he separates the Radiata (_Radiaires_) from the Polypes. His "Radiaires" included the Echinoderms (the _Vers echinoderms_ of Bruguière) and the Medusæ (his _Radiaires molasses_), the latter forming the Discophora and Siphonophora of present zoölogists. This is an anticipation of the division by Leuckart in 1839 of the Radiata 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[121] published in 1798, we find that in the most important respects, _i.e._, the foundation of the classes of Crustacea, 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 céphalés and Mollusques acéphalés being much less natural. With the elimination of the Mollusca, Cuvier allowed the Vers or Vermes of Linné to remain undisturbed, except that the Zoöphytes, the equivalent of Lamarck's Polypes, are separately treated.