298 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Feb. 9,
ends of the long axis than elsewhere (in sections). The calice is not
shallow, is elliptical, and presents, deeply seated, a long lamellar
columella, which is joined to the primary and secondary septa by processes.
The septa are well developed and plain ; they are not exsert,
but pass straight downwards and inwards towards the columella ;
they do not correspond to the costae, but to the intervals between
the costae, and they number thirty-two. There are three cycles,
with the orders of a fourth, in two systems.
Height 1/2 inch. Breadth 1/4 inch. Small diameter, halfway, 1/10 inch.
Locality. Hamilton, Victoria, South Australia.
6. Sphenotrochus excicus, Duncan. Plate XIX. fig. 6.
The coral is generally much compressed, especially inferiorly, where two lateral processes give a notched or emarginate appearance to the base. Superiorly the relation of the long to the short axis is at least as 2 to 1. The coral is short and broad ; the base is nearly as wide as the calice is long. The costae are large and plain, and are separated by well-marked lines : the costae of the appendices are the largest ; they pass upwards to the calice, and all are more or less wavy, the central widening out near the calicular margin. The calice is shallow and elliptical. The columella is not long, and, from being joined to the primary and secondary septa by processes which are rounded above, is confused in its appearance. The septa are in six systems of three cycles ; they are wider at the wall than elsewhere, and granular, and those of the third cycle are much smaller than the others. All the septa correspond to the depressions between the costae.
Height 1/4 inch. Breadth 2/10 inch.
Locality. Hamilton, Victoria, South Australia.
7. Conotrochus M'Coyi, n. sp. Plate XIX. fig. 7.
The corallum is small, claviform, straight, and marked with strong transverse ridges of epitheca. The calice is circular in outline, and the margin is rather stout. The septa are unequal ; there are three cycles, in six systems; and the primary, which reach the columella, are very stout, slightly arched, and faintly granular. The secondary septa are smaller than the primary, and they occasionally reach the columella ; the tertiary septa are either rudimentary or only faintly seen. The columella is stout, papillary, essential, and projecting.
Height of the corallum 1/2 inch. Breadth of the calice about 1/5 inch.
Locality. 1-1/2 mile west of Cape Otway.
8. Conotrochus TYPus, Seguenza, var. australiensis. Plate XIX. fig. 8. Segu. Disqu. Pal. intorno ai Corall. Foss., Mem. Acad. Turin, tom. xxi. p. 478.
The corallum is small, cylindro-conical, curved and pedicellate. The epitheca is strong, and ridged transversely, and reaches to the calicular margin ; it is marked with wavy lines transversely, and
