Most of the species can be easily detached from the rocks to which they are found adhering, but in some cases it is found necessary to cut out the portion to which they cling, by means of a hammer and chisel. But when this is done, and they are placed in the Aquarium, they often willingly leave the stone to which they are attached, which they would not do by gentle persuasion, or any moderate amount of force; and they then take up their station on some suitable portion of the artificial rock-work, just as those do that have been originally detached from their native rocks. Above twenty species of Actiniæ are known to British naturalists.
Plate IX.
1. Actinia anguicoma.
2. Cucumis hyalinus.
3. Echinus sphæra.
4. Alyconium digitatum.
The Lucernariæ are another class of Zoöphytes, or plant-like creatures, as the term Zoöphyte implies, being formed of the Greek word, Zoön (ξωον), signifying a thing possessed of animal life, and phyton (φυτον) a plant. This general term is applied to all the creatures—some of very distinct character—that belong to this class, which forms a separate division of natural science, known as Zoöphytology.
The species of Lucernaria, which has received the specific denomination of auricula, from its slight resemblance in form to the flower of that name, is delineated in [Plate VIII.], attached to a slender branch of sea-weed, just above the two large Sea-Anemonies. This species of Lucernaria is generally of a light pinkish colour, and is, in general form, perhaps more like a Convolvulus than an Auricula. Two species have been most beautifully delineated in all their details by Mrs. Johnston, in her husband’s magnificent work on British Zoöphytes. These drawings are, in fact, so charmingly and, at the same time, accurately executed, that it would seem that the pencil ought to be guided by delicate female fingers when portraying these minutely-intricate and unusual forms of animal life. The exquisite drawings by Mrs. J. E. Gray, in her work on the curious molluscous animals, whose habitations alone, the beautiful sea-shells of our cabinets, were, till recently, all that was known of them, afford further evidence, if it were needed, of the aptitude of the more finely-strung female capacity for this department of scientific portraiture. The name of Mrs. Griffiths is also honourably associated with the study of natural science, especially that connected with our marine Algæ—a beautiful division of sea-weeds—having received its name Griffithsia, in honour of the esteemed services of that accomplished lady.
The Lucernaria campanulata, which is of a somewhat more bell-shaped form than the preceding, is of an uniform liver colour; and in the hollow of the flower-like cup the “mouth” projects, in a square form in the centre. There are three known species of British Lucernariæ, which would all form highly curious objects in the Aquarium; but they are excessively delicate and fragile creatures, hanging suspended from the object to which they are attached, when taken out of the water, like a mere lump of jelly, and would doubtless be very difficult of transport, and probably not capable of retaining life in a state of confinement, except for a short time.