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A reference to the Plate will show that the habit of the polyzoarium is clearly that of Ramipora, as distinguished from Synocladia, a central or chief stem from which are given off a series of straight non-bifurcating branches, without any separation by longitudinal ridges or keels, beyond that occupying the centre of each stem or branch, and the cells all opening much on the same level; instead of, as in the latter, a series of continually dichotomizing branches, longitudinally divided by several carinæ separating the cells.

The polyzoarium in this interesting Polyzoon was probably openly infundibuliform, or basket-shaped, there being a series of the principal straight stems, all branching off at the base from a common root, or stolon, but in no way bifurcating or springing from one another. Four of these stems are shown in the larger specimen, each giving off laterally, and at subalternate distances, the secondary stems, which, as in the former case, in no way bifurcate or dichotomize, but proceed direct, and intact in themselves, to the periphery of the frond. Here and there however, between two of the secondary stems, similar short (or abortive?) ones arise from the main stem, which unite directly with the cross-bars or dissepiments. As in most of these frondescent Polyzoa, the common root is devoid of pores or cell-openings.

From the secondary stems are given off the interstices, or crossbars, by the union of which are formed the mesh-openings, or what in a Fenestella would be called the fenestrules. These dissepiments spring from opposite sides of each secondary branch at an acute angle, and on a level with one another, and uniting more or less in the middle line between every two contiguous secondary branches, with those arising from the latter give rise to the broadly V-shaped fenestrules. As a rule, great regularity may be noticed in the form of these openings, taking the whole surface of the frond, but here and there an irregularly-formed one is to be met with. The section of the main stems, secondary branches, and dissepiments was biangular or diamond-shaped.

The angular or apical ridge of the various stems and branches of the frond is devoid of any pores, or other features of interest; but on the sides of the main stems, immediately under the apical ridge, are two linear rows of contiguous pores or cells with round apertures, those of the one row being a little subalternate with those of the other. There may be a third row, but I have not been able to distinguish it, and from the width of the lateral portions of these stems I hardly think there is room for the expansion of the cell-mouths. The description of the arrangement of the cells on the main stems will also suffice for that on the secondary stems and the interstices-for I cannot detect any difference in their distribution. The reverse face of the frond is, as before said, angular, but non-celluliferous.

So little has been done in this country towards the elucidation of Silurian Polyzoa, with the exception of the brief original descriptions, mostly by Lonsdale, and scattered through the works of Murchison,' that there is always the chance of re-describing or re1 And those contained in Prof. M'Coy's Brit. Pal. Fossils.

naming some already known form, which may have been noticed from a mere fragment, and that imperfectly-no matter how carefully the literature of the subject is searched.

So far as my acquaintance with British Silurian Polyzoa goes, the only one which could possibly be, in fragments, confounded with that now under description is Glauconome disticha, Goldf. This error has been committed in specimens in the British Museum, and in the Museum of Practical Geology; but after Prof. M'Coy's clear description of G. disticha, an easy separation may readily be arrived at. Fragments of the latter may be at once distinguished from those of Mr. Williams' fossil, by the rounded contour of the stems and branches on the reverse face, and their granular ornamentation, whereas in the specimens now under consideration it is angular, and so far as known without granules or striæ of any kind. Again, as regards the cell-bearing face; in G. disticha the pores are large, oblong, thick-edged, occupying the whole width of the face on each side the central keel, and their ends in contact. In Ramipora, on the contrary, the apertures are round, similarly placed, without elevated edges of any kind, merely forming a series of depressions on the interstitial surface, and separated from one another by an appreciable distance.

It now only remains for us to consider how far this interesting Caradoc fossil agrees with the single species of Ramipora hitherto described, R. Hochstetteri, Toula. The arrangement of the branches, primary, secondary, and ternary, is identical in both; the cross section of the latter appears to be the same. The chief points of difference appear to lie in the greater development of the central keel of the branches, and judging from Dr. Toula's figure, a greater regularity in the disposition of the pores. Finally, taking the whole frond into consideration, the Caradoc form exhibits a tendency towards a less robust habit. Pending a more complete description of R. Hochstetteri, Toula, I fail to see the advisability of establishing a new species for this interesting fossil, but shall at present content myself with considering it as a variety only, under the name of Ramipora Hochstetteri, Toula, var. carinata (mihi). For those observers who prefer to look upon the points above brought forward as of specific value, the designation carinata will, perhaps, be acceptable in that sense.

The undoubted interest attached to this elegant fossil lies in the fact of the extension backwards in time of a form only previously known to exist towards the close of the Palæozoic period.

I am indebted to Mr. G. J. Williams for the loan of his really beautiful specimens. I have also been permitted to borrow a series contained in the Museum of Practical Geology. For the loan of Lonsdale's type specimen of Glauconome disticha, Goldf., contained in the Murchison Collection, I am indebted to the President and Council of the Geological Society. This assemblage of examples, with a few which unexpectedly came to light in the British Museum Collection, has enabled me to study a fine series from the Welsh Caradoc rocks. Localities and Horizon.-"A little south of the town of Corwen," in

beds of Caradoc age (G. J. Williams). Bwlch-y-Gasy, near Corwen, and near Cynwyd, in a micaceous clay slate of similar age (British Museum). South of Cefn Coch, near Llangollen, similar matrix and horizon (Museum Practical Geology).

EXPLANATION OF PLATE VI.

FIG. 1. Ramipora Hochstetteri, Toula; var. carinata, R. Eth., jun. Caradoc, nr. Corwen (Cabinet of Mr. G. J. Williams, Tanygrisian).

la. General view, natural size.

16. Portion of a frond, enlarged about twice (drawn from a plaster cast). FIG. 2. Ibid. nr. Llangollen (Mus. Pract. Geology, nat. size).

FIG. 3. Ibid. nr. Corwen (Brit. Mus., nat. size).

II. ON A NEW GENUS OF FAVOSITE CORAL FROM THE NIAGARA
FORMATION (U. SILURIAN), MANITOULIN ISLAND, LAKE HURON.
By G. JENNINGS HINDE, F.G.S.

CE

ERTAIN zones of the massive grey dolomite belonging to the Niagara Formation in North America are so largely composed of fossil corals as to indicate similar conditions of formation to that of the coral reefs of the present age. Perhaps no better examples of these Palæozoic coral reefs could be found than those which are exposed in many tracts of the surface of the Great Manitoulin Island, which are literally covered with complete and fragmentary corals in a silicified condition, which have been weathered out of the matrix of hard dolomite in which they had been imbedded. The great majority of these corals belong to the well-known genera Favosites, Halysites, Heliolites, Alveolites, Conites, Syringopora, Strombodes, Cyathophyllum, Zaphrentis and Omphyma, and many of the species are also common to the Silurian rocks of Europe. A recent search in the débris of one of these ancient reefs has brought to light a coral which appears to belong to a new genus, with the following characters.

SYRINGOLITES, gen. nov.

Gen. char.-Corallum composite, growing in large flattened masses with a basal epitheca. The corallites are polygonal, comparatively thin-walled, closely in contact, vertical in their direction of growth, and with one or more rows of mural pores on each of their prismatic sides. In the centre of each corallite is a cylindrical tube, with nonperforate walls, formed apparently by the invaginated extension of a series of funnel-shaped tabulæ. This median tube appears to be continuous as a rule, though rarely a thin horizontal plate may be seen crossing it. The upper surface of the funnel-shaped tabulæ carries numerous well-marked rows of short septal spines or tubercles, which converge from the sides of the corallites to the central tube into which they also extend. In certain examples the walls of the calices are crenulated by vertical septal ridges.

Obs. The only genus with which the above is at all closely allied is that of Romeria, Edwards & Haime (Polyp. Foss. des Terr. Pal. p. 253). This genus was formed to include the single species of Calamopora infundibulifera, Goldfuss (Petrefacten Germ. part i. p. 78, plate xxxii. figs. 1 a, b), and is thus described: "Polypier en masse

arrondie, polypiérites unis par leurs murailles; planchers infundibuliformes." In the description of the only species of the genus the authors further add, "Nous ne savons pas, s'il existe réellement des trous aux murailles." The above generic description is of so wide and general a character that it would certainly include my new form, and at first disposed me to refer it to Romeria; but having had the opportunity (for which I am indebted to the obliging courtesy of Professor Andrea, of Bonn) of making a close examination of the original specimens, upon which Goldfuss and Edwards & Haime based their descriptions, I find that the differences are too great to allow the forms in question to be placed in the same genus. Thus in Romeria (Calamopora) infundibulifera, the corallites have unusually thick walls, and are not in contact at their summits, which are circular. There is, further, the very important fact, that no mural pores can be distinguished in the specimens, notwithstanding the statement of Goldfuss that such existed; and the character of the corallite walls, and their separation from each other at the surface of the corallum, tends to negative the probability of their presence. Again, there is no appearance in the type specimens of the open central tube as shown in Goldfuss' figure (plate xxxii. fig. 1 b), but there are, instead, funnel-shaped tabulæ resembling those present in the genus Syringopora, consisting of a series of elongated closed cones closely fitting into each other. The specimens of R. infundibulifera may, indeed, be compared to a Syringopora, in which the connecting processes are absent, and the corallites are in contact with each other. There are, besides, no indications in Roemeria of septal spines. It is thus apparent that there is sufficient divergence in the characters of Roemeria, as shown in the only known examples of the genus, and Syringolites, to justify the separation of these forms into distinct

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A. Fragment of a colony of the natural size. B. A single calice of the same, enlarged eight times, showing the central tube and radiating lines of septal tubercles. C. Part of a corallite of the same, split open and enlarged six times, showing the composition of the central tube out of invaginated tabulæ. D. Part of a corallite of the same viewed from the exterior, and enlarged six times, showing the mural pores.

The only difference between Syringolites and Favosites (Lamarck) (= Calamopora, Goldfuss) consists in the central tube and the rows of septal spines on the tabular surfaces and in the tube of the coral

lites of the former genus; in all other respects, the resemblance between the two genera is very close.

The absence of connecting processes, the mural pores, and the open character of the central tube, sufficiently distinguish Syringolites from Syringopora.

SYRINGOLITES HURONENSIS, sp. nov.

Besides the above-mentioned generic characters, it may be added that the upper surface of the corallum is nearly flat; the walls of the corallites are well defined, and occasionally possess a wavy outline. The calice formed by the uppermost tabula is moderately deep, and gradually slopes from the sides to the central tube. The corallites are of generally uniform size, about one line in diameter, the central tube is about line wide, and the tabulæ are about line apart. There are on the upper surfaces of the tabulæ about twelve complete rows of septal tubercles or spines extending from the sides of the corallites to the central tube, and between these are incomplete rows, which only reach part of the distance. The central tube is of nearly uniform diameter throughout. The mural pores occur at irregular intervals, and appear to alternate with each other.

The specimens are all silicified and free from the dolomitic matrix, so that their characters are very distinctly shown. Not infrequently the central tube has been filled up with silica, and in this condition it presents the appearance of a solid columella, for which it might be mistaken.

Formation and Locality.-Not uncommon in the Niagara dolomite (Wenlock), near Manitouwaning, Great Manitoulin Island, Lake Huron.

III. ON SOME RECENTLY DISCOVERED TEETH OF OVIBOS MOSCHATUS, FROM CRAYFORd, Kent.

TH

By WILLIAM DAVIES, F.G.S.,

of the British Museum.

HE great geological interest which attaches to the fossil remains of the Musk-ox or Sheep (Ovibos moschatus, Blainv.), found in British Pleistocene deposits, and the few instances hitherto recorded of their occurrence (together with a recent discovery brought to my notice), have suggested to me the desirability of a brief enumeration of them.

They consist respectively of a portion of a skull, from the low-level Thames gravel, near Maidenhead, first described by Prof. Owen;1 a fragment of a skull from the gravels of Green Street Green, near Bromley, Kent; both of which are preserved in the British Museum; "fragments of the skulls of a male and female, from the gravels of the Avon at Freshford, near Bath;" a "basal portion of a skull obtained from the gravel of Barnwood, near Gloucester;" and, "a nasal bone, a tibia, and an astragalus, from the low-level gravels of Fisherton," near Salisbury; and, lastly, "the head of a fine bull, wanting the facial bones, discovered and exhumed by Prof. Boyd Dawkins, from the lower 1 Bubalus moschatus, Owen; Quart. Journ. Geol. Soc. vol. xii. (1855), p. 124.

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