THE GROWTH OF JELLY-FISHES.
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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
![](http://upload.wikimedia.org/wikipedia/commons/thumb/8/84/PSM_V33_D763_Larvae_of_cunina_and_hydras_transforming_into_medusae.jpg/400px-PSM_V33_D763_Larvae_of_cunina_and_hydras_transforming_into_medusae.jpg)
Fig. 12.—A. colony of three young parasitic larvæ of Cnnina.
Fig. 13.—An older colony, consisting of six Hydras, some of which have begun to become transformed into Medusæ.