Page:Quarterly Journal of the Geological Society of London, vol. 29.djvu/485

 coryne, a genus of Tubularine Hydrozoa from the Carboniferous formation."

In 1872 Dr. Allman (Monograph of the Hydroida, Ray Society, vol. ii. pp. 172 & 173) criticised the zoological position we had assigned to the fossil, and, whilst expressing his satisfaction concerning the manner in which it had been described and delineated, gave also his reasons for not including Palceocoryne amongst the Hydroida.

Some of these reasons, which are stated with Dr. Allman's usual clearness and force, had occurred to us during the difficult task of assigning a classificatory position to the form ; and we wrote (op. cit. p. 695), "Were it not for the calcareous investment, there would be no difficulty in admitting the fossil amongst the Hydrozoa : and had we not been able to avail ourselves of the affinities of the very anomalous genus Bimeria (Wright), the difficulty could hardly have been overcome."

Lately Mr. R. Etheridge, jun., F.G.S., of the Geological Survey of Scotland, has forwarded to me a great number of fragmentary specimens of Paloeocoryne derived from the lower Carboniferous shales.

These specimens explain certain points of anatomy upon which there was some doubt, and also testify to the correctness of the published descriptions. I have therefore again carefully examined into the whole question of the structures and affinities of the form, and now offer some important additional facts which may influence the decision of palaeontologists with regard to the zoological position of this very anomalous form.

The fossils, specimens of which are very numerous, are found associated in the shales with Fenestellce, Crinoidea, and Brachiopoda. Usually they are attached by a dactylose pseudo-cellular base to the margins of the polyzoaria of Fenestelloe. The cells of the base communicate, and appear to have a distinct reference to the inequalities of the surface on which it rests. They are covered by a calcareous investment, which contracts as the base increases in height and is continued upwards in the form of a cylindrical stem, which is faintly enlarged in its middle portion, and which is surmounted by a symmetrical expansion resembling in position, and somewhat in appearance, the capital of a pillar.

The erect stem and capitulum are about 1/10 to 1/8 inch in height. They were originally hollow, and their cavity was continuous with that of the base. A whorl of elongated and tapering cylindrical processes is given off from the upper margin of the capitulum ; and each process is hollow. The processes open by their cavities into the cavity of the capitulum near its upper part. The upper surface of the capitulum thus surrounded is in some specimens projected to form a slight crateriform opening, or mctastome, which leads down to the cavity within. The calcareous investment of the stem and capitulum is continued on to the processes, and is elegantly ornamented throughout with grooves, lines, serrations, pits, small spinules and granulations. The grooves and linear ornamentation are longitudinal both on the tentacular processes and on the stem ; and the

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