Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/422

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stinct grooves, and are of different lengths, those of the higher orders joining the others, which reach to the base. All are visibly crenulate and faintly granular.

In form the coral resembles a Sphenotrochus ; the papillae on the columella resemble those of Brachycyathus ; the single row of pali and the distinct costae determine it to be one of the Caryophyllioe ; but the absence of an epitheca is remarkable. It is a very beautiful form, and, without its calice, would be taken for an Eocene Turbinolian.

Height 4/10 inch. Length of calice 3/10 inch ; width of calice 2/10 inch.

Locality. Violet Creek, near Muddy Creek, South Australia.

2. Trochocyathus meridionalis, n. sp. Plate XIX. fig. 2.

The corallum is short and hemispheroidal in shape, marked externally by subequal costae and a depression at the base, small and circular in outline. The costae are separated by distinct intercostal spaces, are very prominent at the calicular margin, and faintly marked with wavy swellings, and their external surface near the base has a row of rounded granules. The primary and secondary are slightly larger than the tertiary, and the higher orders are smaller than the latter. The calice is circular in outline, and shallow. The septa are distinct, unequal, distant, and smaller than the costae. They are broad externally and exsert, but they soon become narrow, granular laterally, and depressed below the calicular margin. There are four cycles, in six systems : the primary are the largest, and are connected with the largest and most prominent costae ; the secondary are smaller ; and the smallest septa, i. e. those of the fourth and fifth orders, only unite with the tertiary far inwards. The granules are large, and appear to increase in size towards the columella. There are pali before all the septa except those of the last cycle ; and the upper edges of the septa pass upwards and inwards to reach the pah, which are small, long, and granular. The tertiary pali are more external than the others ; and all are united laterally by a spongy tissue, so as to form a ring higher than the septa in the body of the calice. The ring occupies much space, forms the outside of the columella ; and within the ring is a deep fossula, at the bottom of which the hard and flat centre of the columella is seen.

Height of corallum 3/10. inch. Breadth of calice 5/10 inch.

Locality No. 7, 2-1/4 miles east of the river Gellibrand.

3. Trochocyathus Victoria, n. sp. Plate XIX. fig. 3.

The corallum is subturbinate and compressed. The base is elongate and nearly in the shape of a ridge. The calice is elliptical in shape, and shallow. The costae are slightly waved, distinct, subequal, prominent, rounded, and ornamented on the free surface by circular disks with a central boss-like swelling, or by moniliform swellings covered with a pellucid structure, which, when worn, represents the outside of the disk. They are slightly granular laterally. The calicular margin is broad, and the wall is stout. The septa are