PART III. 



AN 



INTRODUCTION 



TO 



POLYZOA. OR BRYOZOA. 



SUB-CLASS L ECTOPROCTA. 

 Anus outside Tentacle stage. 



Order L Gy mnolaemat a (Holobr an ch iate) , 

 No Epistome. Tentacle stage circular. 



Sub-Order 1 Gyclostomata. 

 * Cell mouth circular, no door (operculum). 



Sub-Order 2 Cheilostomata. 

 Cell mouth with lip-like door. 



Sub- Order 3 Ctenostomata. 

 Mouth of Cell cut into narrow segments 

 closing aperture. 



Order II. Phylactolaemata(Pterobranchiate). 



With Epistome, tentacle stage with arms. 



SUB-CLASS II. ENDOPROCTA. 



Anus within the tentacle stage. No 

 Epistome. Tentacle stage an imperfect circle. 



* Cell or zoosciuin. 



