All the anemones so far briefly described are quite devoid of any kind of skeleton, the whole body being of a pulpy or leathery consistence, but some of our British species develop an internal calcareous skeleton, consisting of a hollow cylinder of carbonate of lime secreted by the body-wall, and attached to the rock by means of a similar deposit formed in the base, and also, within the cylinder, of a number of thin plates attached to the skeleton of the body-wall and projecting inwards towards the axis, thus resembling, in fact, the skeletons of a number of the tropical corals with which we are familiar. The animals in question are often collectively spoken of as British corals. [Illustration: FIG. 100.--_Bunodes gemmacea_, WITH TENTACLES RETRACTED] One of the finest of these corals is the Devon Cup-Coral (_Caryophyllia Smithii_), figured on Plate II. It may be found in many parts of Devon and Cornwall, attached to the rocks between the tide-marks, often in very exposed places, but is much more abundant in deep water. Its skeleton is white or pale pink, and very hard, and is in itself a beautiful object. The animal surrounding this stony structure is of a pale fawn colour, with a white disc relieved by a deep brown circle round the mouth. The tentacles are conical, almost colourless and transparent, with the exception of the deep-brown warts scattered irregularly over them, and are tipped by rounded white heads. Of course a hammer and chisel are necessary for the removal of these corals, but they are hardy creatures, and may be kept for a considerable time in captivity. Their habits, too, are particularly interesting, and two or more may sometimes be found with skeletons attached, suggesting that branched arrangement so common in many of the corals from warmer seas. Another of these stony corals (_Balanophyllia regia_) is shown on the same plate. It is much smaller than the last species, but exceedingly pretty. It is also much less abundant, being confined almost exclusively to the coast of North Devon, and is seldom seen far above the lowest ebb of the tide. [Illustration: FIG. 101.--_Caryophyllia cyathus_]