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Show 1876.] AND LITTORAL CORALS. 441 slightly prominent, unequal, very numerous, perforated here and there, close together, and spinulosely granular, the grains being few and large. There is an epitheca, which reaches upwards from the base a short distance ; and the wall is thin and reticulate. The calicular fossa is wide and shallow; the columella is oval and moderately large ; and there are more than five cycles of septa in each of the six systems. The septa are thin, not exsert, long, and unite not far from the columella, and near the wall the larger are perforate. Height jjj-fe inch. Breadth of calice fV-Aj inch. Locality. St. Helena, on an Ostrea ; probably 11 fathoms. (Sent as having come up with an anchor from a great depth.) BALANOPHYLLIA STRIATA, sp. n. (Plate XLI. figs. 7-9.) The corallite is tube-like, there being but slight alteration in the breadth of the cylindrical and bent form during growth ; it is long, slender, bent, and fixed by a wide base. The costse are numerous, subequal, close, faintly granular; and the synapticulse are visible on the intercostal spaces where the costae have been worn, but not otherwise. There is an epitheca inferiorly. The costse do not project upwards at the calice ; but those of the primary and secondary septa and sometimes of the tertiary are a little higher than the others. The wall is thin at the margin, and the reticulation is slight. The calice is circular in outline, very deep ; and the columella is very small, and appears as a few scattered papillae. The septa are thin, long, not prominent, and do not reach far into the centre at the margin; but the larger reach far inwards at the base of the fossa. The larger are plain, and the rest are denticulate. The union is made close to the wall and halfway down the calice. Height Ife inch. Breadth of calice fe inch. Locality. Found with the species just described. Genus PLACOPSAMMIA, Reuss. P L A C O P S A M M I A D A R W I N I . (Plate X L . fig. 4.) The corallum has a broad ascending base, which narrows suddenly and is continued upwards as a cylindrical tube-like corallum, one diameter being slightly greater than the other. Buds project from the same height as the parent, in a whorl, and pass upwards and outwards. There is no epitheca ; and the costse are well developed, nearly equal, broad, distinct, and sharply multigranular. Theintercos-tal spaces show synapticulse, and are distinct. The calice is elliptical in outline, and rather deep; the margin is densely reticulate and stout; and the septa, barely exsert, are thin, long, and do not project much from the margin. There are twelve nearly equal septa (1 & 2) ; and the tertiaries are not so well developed as those of the fourth cycle. All these last are rather spiny on their internal margins ; and their approach and contact with each other is very slight and low down. There are four perfect cycles, and in one or two systems an order of the fifth. The columella is deeply seated, is well separate |