THE NEW GENEALOGICAL TREE 411 



Coelenterata-the Coelomata, the Radiata-the Bilateria, the 

 Ecterocoelia-the Enterocoelia. The categories Protostomia 

 and Deuterostomia must be therefore abandoned. We find it 

 completely satisfactory if we use the simplified classification 

 of the primarily polymerized animal groups (classes) as mem- 

 bers of the phylum Polymeria. We emphasize explicitly that we 

 speak here of the primarily polymerized animal classes only, 

 because there are also secondarily polymerized animal classes 

 which belong, as we shall later see, to the phylum Chordata. 



The Classes of the Phylum Polymeria 



Just as in the case of the phylum Ameria we find in the 

 Polymeria that the evolution of their basic structural (Fig. 

 56) type had spread radiating into several different specialized 

 directions. The system and the taxonomy of the groups of 

 Polymeria which have emerged as a result of these various 

 lines of evolution have been treated variously by zoologists. 

 The study of these various groups of Polymeria has been made 

 difficult by the fact that the same animal groups were placed 

 into various categorical levels by various authors. There is a 

 considerable unanimity among scholars about the general 

 sphere of the high group of the Polymeria; it corresponds 

 roughly to the old notion of the Articulata as it was proposed 

 by Cuvier.* The word Articulata can be met with not in- 

 frequently even now as a name of a high taxon, e.g. in Bekle- 

 mischew. In this case the two notions and high taxons Arti- 

 culata and Polymeria correspond exactly to each other. Yet 1 

 prefer the name Polymeria because it agrees better with the 

 names of other groups with a similar rank, the Ameria and the 

 Oligomeria, and because it expresses better what it represents ; 

 the Oligomeria are finally also "articulated" animals while at 

 the same time they had evolved separately from the typical 



* Not in the sense of the "Articulata" Huxley (1869) as a subgroup 

 of the Brachiopoda! 



