Page:The Book of the Aquarium and Water Cabinet.djvu/101

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THE MARINE AQUARIUM.
89

The Actiniadæ—so named from the Greek—signifying a ray of the sun—are an extensive family, of which more than a hundred species are to be found on our coasts, or in the deep bays adjacent. But few of these are suited for confinement in aquaria, and of these the chief are the Actinia proper, the Sagartia, most of which are usually grouped with the Actinia; the Anthea Cereus; the splendid Adamsia Palliata, which is the only known species of the genus to which it belongs; and a few of the Bunodes, Edwardsia, and Corynactis.

In all the varieties of sea anemones the mode of life is similar; they are carnivorous, and obtain their prey by means of the ever-seeking tentacles that search the lymph around them, and secure sometimes fishes, at others mollusks, but more frequently the minute forms of infusorial life that abound in the sea, or in the artificial water of the tank. The mode of reproduction is by ova, which are sometimes vivified in the body of the parent, and not only do they give birth by ejection from the mouth of a numerous progeny, but actual divisions of the body may be made, and each division will acquire completeness. Dr. Johnson relates several instances in proof of this, one of which is particularly interesting. A specimen of Actinia crassicornis had swallowed a large, sharp-edged shell, which so completely stretched the body of the creature as if on a ring of wire, as virtually to cut it into two equal parts. Thereupon it put out from the base a new disk, with mouth and tentacles, and became at once a double anemone, to which the gorged shell served as an intermediate base of attachment. Dr. Cocks