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converging to the apex, where they meet at an angle of between seventy and eighty degrees. In one of the two specimens collected, there is a flat margin on each side one-sixth the whole width of the shell. Between these two flat margins the remainder of the shell is gently convex. In the other specimen this central space is slightly convex in the anterior part of the shell, but on approaching the beak it becomes an angular roof-shaped ridge. The shell is thin, black and shining with obscure fluctuating, concentric undulations of growth, and with very fine, obscurely indicated, longitudinal striæ.

Length nine lines; width five lines.

LINGULELLA? AFFINIS, spec. nov.

Fig. 4.

Ventral valve elongate, conical or acutely triangular. Apical angle about 45°. Front margin gently convex in the middle, rounded at the angles; sides nearly straight, uniformly converging from the anterior angles to the beak. Surface with very fine longitudinal striæ, about ten in the width of one line.

This species is founded upon the single specimen of a ventral valve above figured. The upper two-thirds is partly worn away in the middle, leaving only the outline in the stone. It appears to have been, when perfect, gently convex, the rostral portion near the beak semi-cylindrical. Length about thirteen lines, width nine lines.

The dorsal valve has not been identified.

LINGULELLA? SPISSA, spec. nov.

Fig. 5, a, b, c.

Shell sub-pentagonal, or sub-ovate, length and width about equal, sometimes strongly ventricose. Dorsal valve with the front margin straight or very gently convex for about two-thirds the width in the middle; anterior angles rounded; sides straight or slightly convex and sub-parallel until within one-third or onefourth the length from the beak, then converging to the apex, where they form an obtuse angle which varies from 100 to about 110 degrees. This valve is generally very convex, sometimes almost hemispherical, the outline on a side view is rather abruptly elevated in the rostral third, depressed convex for a short space in the middle, and then more gently descending to the front margin. Most of the specimens of this valve are eight or. nine lines in length, and about the same in width.

The shell which is supposed to be the ventral valve of this species, is gently convex, with usually a somewhat flat space extending from the front margin upwards towards the beak. The apical angle appears to be from 90 to 100 degrees. Shell very thick, of a lamellar structure, dark brown or nearly black, and, sometimes, where exfoliated, of an ashy grey colour. Surface with a number of obscure undulations of growth and with fine longitudinal striæ, about ten in the width of one line.

[merged small][graphic]

FIG. 6. Cruziana similis; g, the median groove; r, r, the ridges at the sides.

The specimens are from twelve to fifteen lines wide, divided along the middle by an angular groove, and bordered on each side by a narrow ridge, about one line wide. The space on each side between the median groove and the marginal ridges, are moderately convex and crossed obliquely by numerous irregular raised lines, with furrows between them. These lines usually have the form of a gentle sigmoid curve, sometimes extending quite across, but are often crowded together in a somewhat confused manner, still preserving the general oblique direction. Upon an average there are about ten lines in the length of half an inch. The marginal ridges are sometimes longitudinally striated.

This species has been heretofore referred by me to C. semiplicata, Salter, but although closely allied, none of our specimens agree exactly with the figures of the British species.

Besides the above six species, many of the beds of sandstone of Great Bell Island, are covered with several species of Palao

phycus and other forms allied to Eophyton and Cruziana. To describe these would require further collections. In the upper strata there are yet two or three new species of Lingula, of which we have only fragments.

FOSSILS FROM THE MENEVIAN GROUP.

Below the strata of Bell Island, there are about 2000 feet consisting of sandstones and slates, in which no fossils have been found except a few fucoids. These with the Bell Island rocks may represent the Middle and Upper Lingula Flags. They are immediately underlaid by about 2000 feet of slates, sandstones and limestones, holding fossils which prove them to be of the age of the Lower Lingula Flags, or the Menevian group of Salter and Hicks. Fossils in some of the beds are abundant but very imperfect. The following are all that are sufficiently well preserved to admit of description.

OBOLELLA? MISER, spec. nov.

Shell small, transversely broad ovate, nearly circular, width slightly greater than the length. Ventral valve strongly convex, depressed conical, greatest elevation at about one-third or onefourth the length from the hinge line. The latter appears to be straight and about one-fifth the width of the shell. In the apex, or the most elevated point of this shell, there is an irregularly circular aperture or depression. The dorsal valve is less convex than the ventral but more uniformly so, the greatest elevation near the centre; beak apparently curved down to the level of the hinge line.

Surface to the naked eye apparently smooth, but when magnified showing very fine concentric striæ. The width of the largest specimen of the dorsal valve seen, is about one line; length a little less. This species occurs at Chapel Arm, in Trinity Bay.

Mr. Davidson has figured and described under the name of O. saggitalis, Salter, a species from the Menevian group, North Wales, which is closely allied to this, the only difference, (so far as can be made out without comparison of specimens) being, that the English species is about double the size of ours. As I un

* On the earliest forms of Brachiopoda hitherto discovered in the British Palæozoic rocks; by, Thomas Davidson, Esq., F.R.S., Geological Magazine, Vol. 5, No. 7, July 1868.

derstand Mr. Davidson, what appears to be an aperture, in the apex of the ventral valve, is not truly such, but an impression made in the cast of the interior by a tubercle on the inside of the shell.

STRAPAROLLINA REMOTA, spec. nov.
b

a

FIG. 7. Straparollina remota, a, view of the spire; oblique view of anterior side.

Shell small hemispherical, spire depressed and rounded in outline, height 2 to 3 lines, width 3 to 4 lines, whorls about three, suture deep. The whorls are nearly uniformly rounded, more narrowly so on the upper side close to the suture, and also on the basal side. On a side view the minute apical whorl is scarcely at all seen; the next below it is elevated about half its own diameter above the body whorl. In a specimen 4 lines wide, the width of the aperture is about 14 lines, as nearly as can be determined from an individual partly buried in the matrix. Surface nearly smooth.

Occurs at Smith's Sound, Trinity Bay.

8

FIG. 8. Hyolithes excellens. In these diagrams, n, represents the rate of tapering on the ventral side; b, the transverse section. The dorsal side of b is too broadly rounded.

HYOLITHES EXCELLENS, spec. nov.

Shell usually about two inches in length, tapering at the rate of between four and five lines to the inch. The ventral side is nearly flat or very gently convex; the lateral edges narrowly rounded, in some specimens rounded angular; the most projecting parts of the sides are at about one-third the height; above

this the sides are gently convex, the dorsum more narrowly rounded. The shell is thin, nearly smooth with very fine obscure striæ, about ten in one line. The striæ curve forwards on the ventral side, forming an arc the height of which is equal to about one-third the width of the shell. On crossing the lateral edges the striæ curve backwards, until they reach the most projecting part of the sides, then cross up and over the dorsum at a right angle. On a side view the shell is gently curved upwards on approaching the apex.

A specimen 24 lines in length on the ventral side is 8 lines wide and 6 lines in depth at 20 lines from the apex.

Occurs in the red limestone at Smith's Sound, Trinity Bay.

10

FIG. 9. Agraulos socialis. The head without the moveable cheeks. The glabella is too distinctly defined in this figure.

FIG. 10. แ

strenuus.

AGRAULOS SOCIALIS, spec. nov. Fig. 9.

Head (without the moveable cheeks) semi-elliptical or conical, width at the base a little greater than the length, gently convex. Glabella conical and (including the triangular projection backwards from the neck-segment) about two-thirds the whole length of the head, neck-furrows all across but obscurely impressed ; neck-segment with a triangular projection backwards, terminating in a short, sharp spine. Fixed cheeks gently convex; front margin sometimes with a portion in front of the glabella thickened. Eyes of moderate size and situated on a line drawn across the head at about the mid-length, distant from each other about the length of the head. Surface nearly smooth.

In small perfect specimens no trace of glabellar furrows can be seen, but in some of the large ones four or five obscure furrows are exhibited.

The largest specimen seen is six lines in length and seven in width. It occurs at Chapel Arm, Trinity Bay.

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