THE HYDRA AND ITS ALLIES 



211 



swim away. The jelly-fishes then give rise to the sexual 

 products and discharge them into the water (Fig. 198). 

 In other cases the jelly-fish is formed but never separated 



FIG. 198. Bougainvillea ramosa. A, entire colony, natural size; B, portion 

 of the same magnified; C, immature medusa; dr. c, circular canal; cu, 

 cuticle or perisarc ; ent. cav, enteric cavity ; hyd, polyp or bydranth; hyp, 

 hypostome or manubrium ; med, medusa; mnb, manubrium ; rad. c, radial 

 canal; t, tentacle; v, velum. From Parker's "Biology," after Allman. 

 This is closely allied to the New England B. supercilians. 



