Fig. 67. Flabellum pavoninum (Lesson).
1. Vertical position.
2. Upper edge, with its plates and median thread.
3. Form of the animal.
Of the Occulinæ, the animal is unknown, but it is contained in regular round radiated cells, more or less prominent, and scattered on the surface of a solid, compact, fixed tree-like coral. The individuals dispose themselves in ascending spiral lines, and appear to be regularly dispersed on the surface of the several branches. The typical species, O. virginea, formerly known as the White Coral, although it differs widely in reality from the true Coral, both in its structure and by its star-like polypiferous cells (Fig. 68), is found in the Mediterranean and also in the equatorial seas. Over the specimen we see (2) a portion of a branch magnified, in order that the reader may appreciate numerically the form of polype over its cells.
Fig. 68. Occulina virginea (Lamarck).
The species formerly named Occulina flabelliformis, and which now bears the name of Stylaster flabelliformis, which is represented in Fig. 69, will give an excellent idea of these arborescent zoophytes. The polypidom is in the form of a fan, with many very unequal branches; the larger branches are smooth, the middle-sized are covered with small points. This fine zoophyte is found in the seas which surround the Isle of Bourbon and the Mauritius, a fine example of which is to be seen in the collection of the Museum of Natural History of Paris.
Fig. 69. Stylaster flabelliformis (Lamarck).