The royal natural history . und on the tentacles or capturing filaments; these being provided with elastic,spirally-coiled stalks, but containing no poison. These knobs are beset with stickyglobules, to which small animals, such as minute crustaceans easily become the prey attempt to escape, the spiral thread by which the knobs are attachedbecomes stretched. When the thread is withdrawn, it more or less entangles thevictim, and, being like the knob, provided with a great number of sticky particles,renders escape impossible. These structures are very different from stinging-cells,wh
The royal natural history . und on the tentacles or capturing filaments; these being provided with elastic,spirally-coiled stalks, but containing no poison. These knobs are beset with stickyglobules, to which small animals, such as minute crustaceans easily become the prey attempt to escape, the spiral thread by which the knobs are attachedbecomes stretched. When the thread is withdrawn, it more or less entangles thevictim, and, being like the knob, provided with a great number of sticky particles,renders escape impossible. These structures are very different from stinging-cells,which are useless to an animal after having been once employed. An adhesivecell or knob can act apparently any number of times, being each time drawn backby the spiral thread to its former position. Ctenophores feed upon all kinds of small pelagic animals, especially L^taceans, while they themselves fall a prey to the disc-shaped jelly-fish and sea-anemones. Ctenophores may continue to grow, if uninjured, almost indefinitely,. cydippe (uat. size). CTENOPHORES. 477 or as long as life lasts. Storms, however, destroy them. The largest specimensare, as a rule, found in waters sheltered from the wind. They are to be seenthroughout the whole year, but are most plentiful during the spring months, andbecome rarer towards summer, when some species, such as the Venus girdle, almostcompletely disappear. In the early autumn, however, great swarms appear,especially of Cestus and Beroe. After a spring of active fertility, the larvae, at thebeginning of the hot months, sink down to greater depths, where they grow intoadults, and come to the surface again in swarms in autumn. Insignificant as these delicate creatures may appear, they delight the eye,both while living and after death, by their luminosity. This is principallydisplayed in the walls of the canals below the ribs. It is a curious fact, and oneunique as regards luminous marine animals, that Ctenophora, after being exposedfor only a sho
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Keywords: ., bookcentury1800, booksubjectnaturalhistory, booksubjectzoology
