62 



LIFE BY THE SEASHORE. 



Fam. Lafoeidse. Cups 

 tubular and sessile. 



Fam. Halecidse. Cups 

 in two rows, tubular 

 and sessile, borne on 

 projecting processes of 

 stem. 



Fam. Sertularidte. Cups 

 sessile, sunk in the 

 stem, usually in two 

 rows. 



Fam. riumularidfe. Cups 

 sessile, on one side of 

 stem only, "nemato- 

 phores" present. 



Cups very numerous, springing 

 from all sides of the stem. 



Halecium. Stems peculiarly stiff and rigid. 



Cups alternate, with \ 

 toothed margin and Y Sertularella. 

 an operpulum. 



Cups opposite, stem | 

 made up of V-shaped j- Sertularia. 

 joints. J 



Cups tubular, on one \ 

 side of stem only, in j- Hydrallmania. 

 clusters. 



Cups deeply sunk, \ 

 branches confined to V Thuiaria. 

 upper part of stem. J 



Plumularia. Nematophores distributed 

 along the stem and branches. 



CHARACTERS OF REPRESENTATIVE SPECIES. 

 Fam. Campamilaridce. 



Genus Obelia. Contains a number of species, of which the com- 

 monest is Obelia geniculata. Height about one inch. Stems 

 upright, zigzag, connected at base by creeping stolons, 

 jointed, with stalked cups at the joints. Margins of cups 

 smooth, stalks ringed. 



Genus Clytia. In Clytia johnstoni, which is very common, the 

 stems bear a single terminal cup. Stems ringed at top and 

 bottom, but not in middle ; edge of cup with ten to twelve 

 teeth. Gonothecce either on stems or on basal stolon. 



Genus Campanularia. The commonest species is Campanularia 

 flcxuosa. Stems slender, branched, flcxuous, about one inch 

 high. Cups large, tapering below, with long ringed stalks. 

 Gonothecre large. 



Fam. Campanulinidce. 



Genus Opercularella. In 0. lacerata the stem is under one inch in 

 height, erect, slender, ringed throughout ; cups few, on ringed 

 stalks. Cups with segmented margin, the segments being 

 capable of closing over the opening like a lid (operculum). 

 Gonothecce large. 



