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
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.
