78 HISTORY OF BRITISH ZOOPHYTES. 



Family. I. Polypes naked, or with only a rudimentary po- 



lypidom. CORYNID^:. 

 t Polypes naked. 



The tentacula scattered. CLAVA. 

 The tentacula in one row. HYDRACTINIA. 

 tt Polypes with a horny cuticle. 



The tentacula with globose tips. CORYNE. 

 The tentacula filiform. CORDYLOPHORA. 

 Family II. Polypidom fistular ; the tentacula whorled. 



TUBULARIADJE. 



t The tentacula in a single whorl. EUDENDRIUM. 

 tt The tentacula in a double whorl. 



Polypidom rooted. TUBULARIA. 



Polypidom unrooted. CORYMORPHA. 

 ** Ovisacs in the form of horny capsules or vesicles scat- 

 tered on the polypidoms, and deciduous. SERTULA- 

 RINA, Ehrenberg. 



Family III. Cells of the polypes sessile. SERTULARIAD^B:. 

 t Cells biserial. 



Cells alternate, tubular. HALECITJM. 



Cells vasiform, everted. SERTULARIA. 



Cells conico-tubular, appressed. THUIARIA. 

 tt Cells uniserial. 



