THE GROWTH OF JELLY-FISHES. 



743 



the tentacles, as shown at e in Fig. 13 ; and, folding down toward 

 the mouth, gives rise to a swim-bell and bell-cavity. The larva is 

 then set free, and it escapes into the water as a young jelly-fish 

 (Fig. 14), with an enormous proboscis {d), a relic of its parasitic 



Pig. 12. — A. colony of three young parasitic larvae of Cnnina. 



Fig. 13.— An older colony, coneisting of six Hydras, some of which have begun to become trans- 

 formed into Mednsse. 



