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were found. In different parts of the same layer numerous bones, horns, and teeth of the red deer have at various times been discovered.”
The vertebra is the fifth cervical, and in its shapes and general anatomical characters, especially the concavo-convex nature of the articular surfaces of the centrum, and the foramina at the roots of the transverse processes, bears a closer resemblance to the cervical vertebræ of the larger members of the order Ruminantia than to those of any other mammalian order.
Thinking, in the first instance, that it might belong to the Megaceros hibernicus, I made a close comparison between it and the fifth cervical vertebra of the skeleton of that animal preserved in the Natural History Museum of the University of Edinburgh. It differs, however, in several of its measurements, more especially in the antero-posterior diameter, in which it is considerably shorter. On the whole, it may be said to possess a much more elegant shape than the vertebræ of the Megaceros. In its characters it corresponds much more closely to the fifth cervical vertebra of a bovine animal; and, from its size, it has probably belonged either to the Bos primigenius, or to the great fossil Aurochs, Bison priscus. In confirmation of this opinion, I have the high authority of Professor Owen, to whom I presented a cast of the vertebra some months ago. It may be interesting to contrast for a moment this vertebra with a human cervical vertebra, when the difference between the relative size of the neural canals and the bony processes is at once apparent, the neural canal of the fossil bone being very little larger than the corresponding canal in the human vertebra, whilst the processes of the former are many times larger than those of the latter. The circumference of the fossil, measuring it around the tips of the processes, is 264 inches. From the almost perfect state of the bone, it must have reposed quietly in the position in which it was found, and have been subjected there to very slight external influences.
The tooth found in the same stratum, and in the immediate neighbourhood of the vertebra, is the last pre-molar of the right side of the upper jaw of a bovine animal, probably the Bos primigenius. It has three fange. The inner surface of the crown is convex, the outer concave and sinuous, the extremities projecting into considerable points. A crescentic enainel island lies in the centre of the tooth, the concavity of which is turned towards the sinuous outer surface of the crown, the extremities of the crescent project to the pointed extremities of the outer surface. At the first glance, it might appear as if this tooth were too small for the cranium of so large an animal as the great extinct Bos; but it was found, on trial, exactly to fill the empty socket of the corresponding tooth in the large cranium of this species in the University Museum, already described. On referring to the cranium which belonged to Dr Fleming, I found the corresponding pre-molar tooth still in its 'socket, and presenting exactly the same anatomical characters.
The bones which I have obtained from the neighbourhood of the town of Preston were found in the year 1836, by the workmen employed in digging the foundations for the piers of the railway bridge over the River Ribble. They were preserved by Mr Joseph Thornber, and by him presented to S. B. Worthington, Esq., the engineer to the Lancaster and Carlisle Railway, who deposited them in the Museum of the Lancaster Mechanics’ Institution.
Mr Thornber, in a note which he has furnished me with, states that the bones were found in a stratum of gravel and sand beneath the peat. This stratum rested on a bed of new red sandstone. One of these bones is an undoubted relic of the Bos primigenius. It was found 26 feet 10 inches below the surface. It consists of the left frontal bone, with the horn-core still attached to it, and springing from the left extremity of the great posterior ridge. The bone has evidently belonged to a young animal, for it has separated from the adjoining bones along the lines of the different sutures, so that it could not have been permanently connected to them by ossification. Its dimensions, also, are much less than those of the corresponding bone in the adult crania, already described, its length being only nine inches, and the circumference of the root of the horn-core nine inches. The core is much less tuberculated, and not so strongly grooved as in the adult specimen. The other bones consist of a portion of the base of of the cranium, a portion of a rib, and the left innominate bone. Of these, it is probable that the first-named only has belonged to a bovine animal. This consists of the basilar process, occipital condyles, and the remaining portion of the ring of bone which surrounds the foramen magnum. It is difficult to say with absolute certainty what animal the other bones had formed a part of. The rib scarcely appears to be bovine, for it is thicker and more massive; the ridge upon its outer surface is proportionally much stronger, and there is only a trace of a groove upon its inferior margin.
The innominate bone is much more slender than the pelvic bones of the existing species of Bos. On comparing it with the corresponding innominate bone in the skeleton of the Megaceros in the Natural History Museum, so many points of similarity were found between them, that I felt inclined to pronounce it to be the innominate bone of the great extinct Irish elk; but, on closer inquiry, I learnt that it is very doubtful if many of the bones in that skeleton are genuine bones of the Megaceros, no less an authority than Cuvier, in the fourth volume of the “Ossemens Fossiles,” stating, in some critical remarks which he makes upon an engraving and measurements of the skeleton transmitted to him by the late Professor Jameson, " that it is doubtful whether the pelvis is well authenticated, seeing that it is not so altered as the rest of the bones.” I find that the innominate bones have been painted dark brown, so as to give them the same colour as the other bones of the skeleton; and on scraping off the paint, a clear white osseous surface is seen beneath.
It is probable that this innominate bone belonged to an animal of the genus Equus, for both in size, shape, and osseous markings, it corresponds most closely with the left pelvic bone of the horse. If this be the case, it adds another to the localities, cited by Professor Owen, in which the remains of this animal have been discovered, and from having been found in the same stratum as, and in the immediate neighbourhood of, the frontal bone of the Bos primigenius, it establishes the coexistence of these different genera in our island.
Mr David Page stated instances of the occurrence of the
Bos primigenius in the north of Scotland ; and Dr J. A. Smith mentioned that its remains had been found in Selkirkshire and Roxburghshire, and referred to notes he had collected some time ago, in regard to the skulls preserved in the Museum of the Society of Antiquaries of Scotland, which he might lay before the Society at another meeting.
II. On Goodsirea mirabilis, an undescribed Gymnopthalmatous Medusa.
By T. STRETHILL WRIGHT, M.D., &c. Three specimens of this medusa were taken in the Firth, near Queensferry, in September last, one of which the author placed on the table this evening. In general form it resembled the Plancia gracilis of Forbes; but it differed from that animal in the shape of its smaller tentacles, the absence of eye-specks, and the presence of auditory organs. The disc was hemispherical, depressed, in some specimens elevated in the centre, and about an inch in diameter. Its margin was furnished with two large colourless tentacles, which were capable of being produced to the length of about two and a-half inches. For about one-third of their length they were hollow, and permeated by the circulating fluid of the lateral canals. The proximal portion of the large tentacles was covered with long, narrow, curved thread-cells, arranged in clusters or cones, like the piled muskets of a regiment of soldiers. These, towards the distal ends, became mixed with large, scattered thread-cells, of an ovate, or rather almond shape, in the interior of which a long, loosely-coiled, smooth thread was very distinctly visible. The tips of the large tentacles were almost entirely furnished with the last kind of thread-cell. In addition to the large tentacles, the margin of the disc bore ninetysix small tubercles, each of which was connected with two exceedingly minute and delicate tentacles, of very complicated structure. The tubercles themselves were covered with the long, narrow thread-cells above-mentioned. The proximal ends of the smaller tentacles, for about one-third their length, were destitute of thread-cells, but were furnished with very thick, short palpocils. This portion of the tentacle terminated in a knob or swelling, which was covered with exceedingly minute thread-cells; then succeeded a portion formed of
nucleated cells, joined end to end in a single row, which portion terminated in a long ovate head, closely set with the large almond-shaped thread-cells, which were found on the tips of the larger tentacles. All these tubercles and their tentacles were destitute of ocelli. Eight otolitic sacs were attached to the exterior of the circular canal, each containing about four otolites. The sub-umbrella was formed by four lateral canals, with their connecting membrane. Its upper part dipped downward so as to form a funnel, from the end of which the peduncle or alimentary polype was suspended. The peduncle, about an inch and a half in length, was very extensile, and of a greenish white colour. It was terminated by a quadrangular campanulate mouth. The peduncle in the
ovaries, which passed along its whole length, and contained countless eggs. In the male it was cylindrical, and included a mass of spermatozoa between its ectodermal and endodermal layers. The whole of the lateral and circular canals were powdered, as it were, with dark purple pigment granules. When floating in the sea, or jerking itself along by the rapid strokes of its disk, this medusa was only rendered visible by the snake-like motions of its peduncle and tentacles. All the rest of its body was as transparent as glass. In a well-lighted jar of sea-water, the outer surface of the umbrella glowed with tints of blue, purple, and amber, reflected from the thin ectodermal membrane, which covered the gelatinous umbrella. With regard to this gelatinous structure, Dr Wright had come to the conclusion that it was not the homologue of the ectoderm of the polype, but rather a true corallum, homologous with the horny plate of Velella and the corallum of Hydractinia. Did it consist of ectoderm, it would be rendered opaque by alcohol, which was not the case, as might be seen in the specimen on the table. In captivity these animals floated near the bottom of the jar in which they were confined, supporting themselves on their tentacles and peduncle, with which they were constantly searching the bottom, as if for food. One of the females discharged a large number of ova, which were carefully preserved in a proper vivarium, and watched, but no farther development took place in them. Dr Wright bad