II. This form is unlike any other from the British and Belgian crag deposits, and does not resemble any species from the Sicilian Tertiary deposits, from the Miocene of Western Europe, from the Eocene of England and the Paris basin, or from the littoral or deep-sea zones of the North Atlantic and Mediterranean Sea.
The closest approach in structural resemblance is in the instance of Trochocyathus meridionalis, Duncan[1], which is a characteristic coral of the mid-tertiary deposits of Australia; the dense epitheca of the crag form distinguishes it at once; and the difference thus determined is specific.
The Trochocyathi of the type of Trochocyathus Burnesi, D'Archiac, from the Nummulitic strata of Sindh, and the subhemispherical Trochocyathi from the British Gault and Oolites foreshadowed the peculiar species iinder consideration.
The genus Trochocyathus has not yielded any recent species as yet; and the dredgings and searchings of the littoral and sublittoral zones of the British coasts have not produced a specimen. M. de Pourtales describes, with an expression of doubt, a worn coral from the Florida region as a recent member of the genus.
The distinctive characters of the new species are the dense epitheca, the small and prominent columella, and the inverted calicular margin.
III. The new species from the Red Crag belongs to the solitary or simple type of Madreporaria, which does not contribute forms to coral reefs. It may be compared with the broad-based Caryophyliæ of the Devonshire sublittoral zone in a technological sense; and it was probably a dweller in shallow water, on roclis where there was no mud accumulating.
The coral fauna of the Upper Tertiaries of England consists of six species:—
1. Sphenotrochus intermedius, Münster, sp.
2. Trochocyathus anglicus, Duncan.
3. Flabellum Woodii, Ed. & Haime.
4. Cryptangia Woodii, Ed. & Haime.
5. Balanophyllia calyculus, Wood.
6. Solenastræa Prestwichi, Duncan.
Sphenotrochus intermedius, under a variety of Synonyms, exists off Cornwall, the west coast of Ireland, and Arran. It is a very common species in the Bay of Tangier, in the Straits of Gibraltar.
Trochocyathus anglicus, Duncan, is not represented, so far as the results of recent explorations tend to prove, in the existing European coral fauna.
Flabellum Woodii, Ed. & H., is represented by a fine Flabellum which is found in the neighbourhood of Cape Spartel, in the S.W. of Spain, in deep water. The curious Cryptangia Woodii, Ed. & H., belongs to a genus which appears to have become extinct during the age of the Crag.
There are many species of Balanophyllia in the North-Atlantic and Mediterranean area and on our coasts; and the Crag form indicates great vigour of coral life and abundance of food. It is extinct,
- ↑ Quart. Journ. Geol. Soc. vol. xxvi. p. 296, pi. xix. fig. 2.
