without assigning to it any specific name, only one specimen being known to me. Since then additional material has been obtained, and Mr. Davidson has done me the honour, in the lately published Supplement to his "Monograph of British Carboniferous Brachiopoda," to connect my name with it. The additional specimens have been obtained chiefly by Mr. Bennie in the East of Scotland; but some time ago I was shown examples collected in the West by Mr. John Smith of Kilwinning. Those gathered by Mr. Bennie prove that in some an additional rib occurs on each side of the fold of the dorsal valve, and that in fact the ribs are mere rounded undulations of the surface of the valves, rather than true ribs in the sense in which the term is usually applied in the Brachiopoda. The surface of the type specimen was smooth, but in one or two there are traces of papillae, as in other forms of Spiriferina.

Locality and Horizon.-Bruntsfield Colliery, near Penicuick, in shale above the No. 2 Limestone of the Lower Carboniferous Limestone group (Mr J. Bennie).

4. Notes on Chonetes polita (M‘Coy), Pl. VI., figs. 2 and 3.— In the Geological Magazine for March, 1878, I briefly referred to the occasional ornamentation of this shell with faint radiating ribs, a peculiarity not mentioned in the original description by Professor M'Coy, nor in Mr. T. Davidson's later remarks. Some examples of C. polita appear to be quite smooth, others, on the contrary, have unquestionable traces of close rounded faint and direct radiating striae, covering the whole of the ventral valve, and usually more apparent from the visceral region forwards, leaving the latter more or less smooth.

Locality and Horizon.-Catcraig Quarry, near Dunbar, in shale above the Catcraig limestone; Ladedda Quarry, near Ceres, Fife, in shale above the limestone; both horizons in the Lower Carboniferous limestone group (Mr. J. Bennie).

5. On the punctate structure of the shell in Orthotetes crenistria (Phill.), Pl. VI., figs. 6-8.-Some time ago very fine examples of Orthotetes crenistria, var. senilis (Phill.), were forwarded to me by Mr. R. L. Jack, F.G.S., from the Permo-Carboniferous beds of Northern Queensland for description, and certain of them for presentation to the Geological collection of the British Museum. The Queensland specimens have, in common with British examples, the semi-conical ventral valve, with step-like interruptions pro

duced by two or three very large and irregular concentric undulaations, the elevated but not incurved beak, and the wide area, with its convex deltidium. Similarly the dorsal valves of these specimens exhibit the straight hinge line, and evenly convex surface. The situation of the valves likewise appears to be identical, and there also appears to be the same concentric lamination of the area and deltidium as seen in some British specimens. The most interesting point, however, is the structure of the shell itself. This is seen to be distinctly punctate, and when the surface is at all worn the punctae are everywhere visible, more especially on the area. I believe this feature in Orthotetes (= Streptorhynchus) has not been generally recognised, for in the generic description given by the best authorities the shell is said to be impunctate. Professor William King, however, has not omitted to notice this peculiarity in a Permian species, O. pelargonatus (Schlotheim). On mentioning the existence of these perforations to Mr. T. Davidson, he informed me that he had recently seen the same structure in some British Orthotetes. The punctae on the exterior of the shells appear as small rugosities scattered at random over the surface of the ribs or striae and intervening valleys, but when the surface is to any extent worn, their perforate character at once becomes apparent.

Locality and Horizon. --Havilah-Byerwin Road, one mile south of Rosella Creek Crossing, Bowen River coal-field, N. Queensland; a marine band intercalated in the "fresh-water" or upper series of the Permo-Carboniferous formation (Mr. R. L. Jack, F.G.S. ).

6. On a small, distorted, and probably young form of Chonetes, from the Carboniferous beds of the East of Scotland, Pl. V., figs. 1 and 2; Pl. VI., figs. 4 and 5.-Only one valve of this shell is known to me—the ventral. When the normal form is preserved the shell is convex, markedly so in the middle line, giving rise to a rather prominent fold of greater or less dimensions. The specimens undergo curious contortions of outline, due perhaps, to a certain extent, to accidental crushing; in some there is a pinching up of the mesial fold or visceral region, in others a puckering in of one of the lateral margins, giving to the valve that irregular appearance assumed by Mollusca which live in crevices and cracks of rocks. One individual is of a very peculiar form―much elongated laterally, and correspondingly narrowed across the valve from the dorsal to the front margin, and somewhat obliquely twisted. The hinge

line is as wide as the valve, and is bordered by a row of hinge spines, rather strong for the relative size of the shells. The alar expansions are small and the angles rounded. When not distorted the valve acuminates or narrows towards the front, and the form is, speaking in a general way, roughly triangular. The beak is much incurved, overhanging the umbonal region of the shell. There is a small, although well-marked and distinct area (Pl. V., fig. 2), which appears to be longitudinally striated, and perforated by a small foramen or deltidial aperture, elongately triangular in shape. The surface is covered with coarse, strong, radiating ribs, which are simple, as a rule, but occasionally bifurcate, and are separated from one another by valleys about their own thickness in width. The ribs vary from sixteen to eighteen in number. The internal characters cannot be distinguished, except that the radiating ribs are as plainly visible as on the exterior. It is difficult to express an opinion as to the specific identity of these little fossils. The question arises, Is the irregular form an accidental peculiarity, or a specific character? If the former, which it probably is, we are dealing with an abnormal variety of Chonetes Buchiana (De Koninck). My friend, Mr. T. Davidson, was kind enough to examine the whole of the specimens, and wrote me as follows:-"I have seen young shells of Chonetes Laguessiana, or even C. Buchiana, very like your specimens. When C. Laguessiana is very young the ribs are simple, and it is only when the shell gets older that the ribs appear to become more numerous by interpolation. I would have put them down for young specimens of C. Laguessiana. It is always very difficult to determine young shells of closely-allied species, for they rarely show the characters of the adult." If these specimens are to be regarded as the young of either of the above species, I think the decision must rest in favour of C. Buchiana, to which they appear to bear a closer resemblance than to C. Laguessiana.

Locality and Horizon.-Skateraw Quarry, near Dunbar, in shale over the Skateraw limestone; Kidlaw Quarry, near Gifford, Haddingtonshire; East Salton old Quarry, ditto, in shale above the No. 2 limestone; Inverteil Quarry, near Kirkcaldy, in shale over the main or No. 1 limestone; Cowdens Quarry, near Dunfermline, a shale over the Linn limestone; all horizons in the Lower Carboniferous limestone group (Mr. J. Bennie).

7. On a small specimen of Orthis perforated by a Crinoid stem,

Pl. V., figs. 4-6.-The shell in question possesses to a great extent the characters of Orthis Michelini (Léveille), having the outline of this species, and the surface of both valves entirely covered with small, straight, short spines. The valves are in apposition, but have been pressed quite flat, or nearly so.

The chief point of interest lies in the presence of a Crinoid stem, which has passed through one corner of both valves, projecting beyond. It is difficult to determine the manner in which this has been accomplished. Had accident forced the encrinite stem through the valves, we should have expected to find the shell fractured to a greater or less extent-but this is certainly not the case and a disarrangement of the surface. On the other hand, we cannot suppose there is, in this case, an attempt at attachment such as we now know took place in some Brachiopoda, otherwise the stem of the Crinoid would have been united to the Orthis either by some portion of the hinge, or the general surface of one of the valves.

Presuming this to be only an accidental occurrence, it is worthy of illustration as showing one of the many facts which have to be taken into account in dealing with the peculiarities of supposed adherent Brachipods.

Locality and Horizon. -Skateraw Quarry, near Dunbar, in shale above the Skateraw limestone (Mr. J. Bennie).

EXPLANATION OF PLATE V. (figs. 1 to 7).

FIG. 1.-Chonetes, sp.-Another example of the shell represented in Plate VI., figs. 4 and 5, exhibiting one of the forms of distortion. Kidlaw Quarry, near Gifford, Haddingtonshire.

FIG. 2.-Interior of another specimen, with the area preserved. Skateraw Quarry, near Dunbar; Lower Carb. limestone group.

FIG. 3.-Lingula mytiloides (Sow.)-A group of four individuals, with the remains of radiating colour bands. Roof-shale of "Smithy" coal, Chance Pit, Bo'ness coal-field.

FIGS. 4-6.-Three views of a small Orthis (near O. Michelini, Lév.), perforated by a small Crinoid stem. Skateraw Quarry, near Dunbar.

N.B.—The natural size of the fossils is shown by the indicators. The originals of Plate V., figs. 1-6, and Plate VI., figs. 1-5, are in the collection of the Geological Society of Scotland. Those of Plate VI., figs. 6-8, are in the British Museum.