Other jelly-fishes, some of which are considerably larger than Aurelia, frequent our seas, and are often to be seen stranded on the beach. Two of these—Rhizostoma and Chrysaora—are figured. Although they differ considerably in form from the blue aurelia, they closely resemble it in general structure and habits.
Fig. 87.—Rhizostoma
Fig. 88.—Chrysaora
When strolling on flat, sandy beaches, especially in the spring and early summer, we commonly see what appear to be little balls of exceedingly transparent and glassy jelly, no larger than an ordinary marble. If picked up and examined, we observe that they are not quite spherical, but oval in form, with a little tubercle at one end, and eight equidistant bands running from this to the opposite end, like the meridians on a globe.
This extremely beautiful little creature is one of the cœlenterates, belonging to the division Ctenophora, or comb-bearing jelly-fishes, so called because they possess comb-like ciliated plates, and is called the Globular Beroe (Cydippe pileus).
The ctenophores are very active creatures, swimming freely in the open seas by means of their numerous cilia; and, although of such delicate structure, are very predaceous, devouring small crustaceans and other marine animals. They are usually globular in form, but some are like long ribbons, and almost all are remarkable for their wonderful transparency, which renders them nearly invisible when floating in water. They have not the power of stinging or paralysing their prey, as the medusæ have, but their fringed arms are provided with adhesive cells by which they hold their prey tenaciously.