IX 



THE HISTORY AND SCOPE OF ZOOLOGY 



385 



Phylum INFUSORIA 



Class. 



Grade a. CILIATA. 

 Branch a. Gymnostoma. 

 1. HOLOTRICHA. 



Branch b. Trichostoma. 



1. ASPIROTRICHA. 



2. SPIROTRICHA. 



Grade b. SUCTOKIA. 

 1. ACINETARIA. 



Phyla and Classes of the ENTEROZOA 

 (syn. METAZOA). 



Sub-Grade a. Ccelentera. 



Class. 



1. CALOISPONGIJE. 



2. SILICOSPONGLE. 



1. HYDROMEDUSJE. 



2. SCYPHOMEDUSJE. 



3. ANTHOZOA. 



4. CTENOPHORA. 



1. Phylum PORIFERA 



2. Phylum NEMATOPHORA. 



Sub-Grade b. Ccelomata. 



Phylum 

 PLATYHELMIA 



Phylum 

 ECHINODERMA 



Branch a. 

 CILIATA 



Branch 6. 



COTYLOPHORA 



Branch a. 

 AMBULACRATA 



Branch b. 

 TENTACTJLATA 



fl. RHABDOCCELA. 

 | 2. DENDROCCELA. 

 { 3. NEMERTINA. 



4. ORTHONECTIDA. 

 U. RHOMBOZOA. 

 I 1. TREMATOIDEA. 

 J 2. CESTOIDEA. 

 ( 3. HIRUDINEA. 



1. ECHINOIDEA. 



j 2. HOLOTHURIIDEA. 

 K 3. ASTEROIDEA. 



(4. OPHIUROIDEA. 



( 1. CRINOIDEA. 



2. OYSTOIDEA. 

 13. BLASTOIDEA. 



