SCYPHISTOMA, 8TROBILA, EPHYRA. 



125 



anterior part of the body, giving rise to a series of segment-like 

 divisions. The anterior part of the body bearing the tentacles is 

 first marked off; and following this a greater or less number of 

 sections, the new segments appearing continuously in the direction 

 from before backward. The hindermost or basal swollen club-shaped 

 end of the polyp's body remains undivided. The Scyphistorna has 



FIG. 113. e, Stage of Scyphistorna with sixteen arms (slightly magnified); Giv. gastric ridges. 



/, Commencing strobilization. 



now become the Strobila, which itself passes through various 

 developmental phases. The tentacles abort ; the successive segments, 

 separated from each other by constrictions and provided with lobe- 

 like continuations and marginal bodies, become transformed into 

 small flat discs, which become separate, and, as Ej)kt/rce, represent the 

 larvae of the Scyphomedusse (fig. 113 b-li). 



