9 o 



SYNCORYNA SARSIL 



PART III. 



The Corynidae form the first of the three families of 

 the oceanic hydra zoophytes. They comprise six genera, 

 and many species of compound animals of various forms, 

 each derived from a single animal by budding ; and 

 although they possess a thin flexible coat, the polypes 

 are sheathed either in a thin membrane or bone. Their 

 club-shaped tentacles form either a single or double 

 circlet round the base of their conical mouth, and are 

 also scattered over their bodies when bare. 



The zooids are developed at once in the Syncoryna 

 Sarsii, which is a long, thinly branched, and horny 



zoophyte, with a single 

 naked, spindle - shaped 

 polype at the extremity 

 of each branch, as in 

 fig. Ill, A. The bodies of 

 the polypes are studded 

 with numerous tentacles, 

 among which buds appear 

 (fig. Ill, a, 6) ; these gra- 

 dually expand into bell- 

 shaped medusa-zooids (fig. 

 Ill, c),some being mascu- 

 line and others feminine. 

 They drop off their parent, 

 swim away by the con- 

 traction of their bell, and 

 their fertilized eggs are 

 developed into single 

 hydrse, which become ar- 

 borescent like their parent 

 by budding. 



Fig. 111. Syncoryna Sarsii with Medusa- The family of the Ser- 



tulariidse take branching 



forms, sometimes of perfect symmetry : they have a firm, 

 horny coat, which not only covers the stem and branches, 

 but becomes a cup for the protection of the polype. 



