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Show 62 MR. J. Y. JOHNSON ON T H E [Jan. 17, necks, already described as being found in both the preceding species ; (2) the short, stout, cylindrical spicule with two whorls of four rays, the " octoradiate spiculi" of Ridley, also present in the cortex of the two foregoing species, but here the latter is more regular and symmetrical; (3) a form bearing a general resemblance to (1), but with the united bodies more elongate, and each member pear-shaped or poke-like and smooth. This form is peculiar to the present species. (See Plate VII. figs. 2 & 5.) This species occurs very rarely, but it is met with rather more frequently than any of the others. Only five specimens are known to me, the largest of which, as well as the one first discovered, were presented to the British Museum. The former of these has a height of 210 millim. (8 in.) and a spread of 315 millim. (12 in.). The stem, before it begins to throw off branches, has a thickness of 27 millim. Fortunately the base came up with the rest; it is a thin plate measuring 83 by 70 millim. There are four principal branches, which are again divided and subdivided in an irregular manner. At one part there are three overlapping layers of branches and in another two overlapping layers, but no instance of two branches meeting and uniting. Another fine specimen in an excellent state of preservation was secured by the Rev. Padre Schmitz for the Seminario Museum, Funchal. It has the same height as the preceding but is not so wide by 50 m m . The coral is curved from side to side, so that the polype-bearing face is convex and the other face concave. The base has been left behind, the stem having given way at a place where it had been much perforated by boring animals. The section here measures 22 millim. by 18. There are five main branches, the longer axes of which measure from 10 to 15 millim. O n the posterior side three secondary branches strike off from main branches at angles which are more than right angles above and consequently less below. The specimen is figured on Plate VI. A third, much smaller specimen is in m y possession. The underside of the spreading base, 55 millim. by 40, the longer axis being nearly parallel with the plane of the branches, is flat with a smooth surface, and bears impressions of three species of creeping bryozoa that had settled upon the supporting body before the coral grew over them. I have also one valve of the great sessile cirripede, Pachy-lasma giganteum (Phil.), measuring 36 millim. by 22, the exterior of which is completely coated with the ccenenchyma of the coral, and this has thrown up several polype-cells, but has not secreted a stony basis. This shows that the polypes secrete the hard compact axis simply as a support for the increasing colony. In M . H . Filhol's work on the submarine explorations of the ' Talisman ' (1884), he says that at the Cape Verd Islands, " entre 500 et 600 metres nous avons rencontre une forme d'alcyonaire extremement interessante au point de vue zoologique, appelee par M . Marion Coralliopsis perieri. Elle rappelle beaucoup le Corallium secundum de Dana vivant aux iles Fidji." This may have been an example of Pleurocorallium johnsoni. |