Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/437

1870.] margin is often wavy. There are six systems, and five incomplete cycles. The lateral crests form an angle of about 60°.

Height of coral 1 inch. Length of calice 9/10 inch.

Locality. Muddy Creek, South Australia. No. 9, 3 miles west of the river Gellibrand.

Variety bursarius with the lateral crests forming convex prominences.

This genus forms part of that named and described by Milne-Edwardsand Jules Haime as Palæocyclus, and it is proposed for the reception of Trochoseris Woodsi, nobis (Ann. Mag. Nat. Hist. Sept. 1864). There was some doubt concerning the genus of T. Woodsi when the species was described, because its anatomical details clearly pointed out Paloeocyclus as the genus under which it should be arranged. But Paloeocyclus is a Silurian genus, the only one of two Fungidae in the Palaeozoic coral-faunas. A careful examination of the species described under the generic term Paloeocyclus was undertaken (see Phil. Trans. Roy. Soc. 1867); and I found that they could not be admitted amongst the Fungidae at all, as they did not possess synapticulae and did possess tabulae. The Paloeocycli of Edwards and Haime are truly paleozoic forms, and are Cyathophyllidoe. An examination of the species Woodsi decided my referring it no longer to Trochoseris but to a genus which would replace Paloeocyclus more in name than in minute anatomy.

The genus must be classified with the Lophoserinae.

The corallum is simple, turbinate, and pedicellate. The septa are numerous. The epitheca is complete and dense, covering the costae. The columella is rudimentary.

15. Palaeoseris Woodsi, Duncan. Plate XX. Fig. 7. Trochoseris Woodsi, Duncan.

The corallum is fixed by a small pedicel, and is cylindro-conical and turbinate in shape. The calice is widely open, circular, and shallow ; the margin is thin. The septa are not exsert, but are delicate, crowded and rather subequal ; there are six systems, and five cycles, with the half of a sixth, in each system. The smaller septa generally join the larger ; and these reach the central fossula. The laminae are marked laterally by synapticulae. Height 7/10 inch. Breadth of calice 6/10 inch.

Locality. Muddy Creek, South Australia.

16. Cycloseris tenuis, n. sp. Plate XX. fig. 8.

The corallum is circular in outline and very thin ; it is slightly convex centrally, where there is a shallow elongated fossule ; and there is a decided concavity inferiorly, marked with numerous costae. The septa are distinct, distant, very slightly marked with rounded dentations ; and there five cycles, incomplete and in six systems.

Height 2/10 inch. Breadth 1/2 inch.