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The following paper contains a description of an unusually perfect dorsal vertebral centrum of Ornithopsis , additional information respecting the cervical and anterior dorsal vertebrm, and a comparison of its prmsacral vertebrm with those of several recently discovered Colorado Dinosaurs, bringing out several concordances but also such differences as prove the generic distinctness of Ornithopsis . Our knowledge of the skeleton of this remarkable Wealden Dinosaur is still so incomplete that I deem myself fortunate in being able to submit to the notice of the Society an unusually well-preserved vertebral centrum, which I obtained from the sea-cliff, near Chilton, Isle of Wight, in 1875 ; the description of which and the remarks that follow may be regarded as a continuation of two former notes on the vertebrae of this Saurian*. This new centrum (No. 178, Coll. H†) (fig. 1), like that with which I identified my neural arch (No. 67, Coll. H) in the summer of 1870 (the Mantellian fossil, No. 28632, Brit. Mus. Catal., Wealden, S.E. England), is characteristically opisthoccelous, the posterior cup being deeply hollow, and the anterior convexity correspondingly prominent. The contour of the articular ends is oval, the longer diameter vertical, the upper end of the oval cut off. In its present state the vertical diameter of the posterior surface is about 3·5 inches, the horizontal diameter about 2·9 inches ; but these measures must be regarded only as approximative, because the edge of the cup is worn, and the whole form is slightly distorted by pressure. I

In the 13th Decade of the Memoirs of the Geological Survey of the United Kingdom, published in 1872, I described the above-named fossil fishes from the Lias formation of Lyme Regis. Since the issue of that publication I have obtained specimens elucidating parts which were defective in the former examples, and which I consider of sufficient importance to warrant description. On referring to the figure of the former ( Platysiagum ), given on plate 6 of the Decade, it will be seen that the dorsal and anal fins are wanting. This also happens with the several specimens described in the text but not figured. These desiderata are furnished by a fine specimen recently obtained. The two extremities are wanting; the remainder of the fish measures 15 1/2 inches in length. It corresponds very closely in size with the larger of the two specimens described in the Decade. The total length of the fish, if restored, would probably be about 22 inches. The vertical diameter of the trunk is very uniform between the occiput and the dorsal fin, and measures 4 inches. This is a singular character in a Sauroid fish, in which family the body is generally fusiform, tapering gradually from the thoracic arch to the commencement of the caudal fin. The dorsal fin which is here preserved is very singular both in position and structure. It is situated 9 1/2 inches behind the occiput, and occupies a position vertically opposed to the interval between the ventral and anal fins, and extends thence nearly

The fossil imbedded in the mass of Pictou Coal, from Nova Scotia, submitted to my inspection by the President of the Geological Society, consists of the anterior extremity of the cranium and upper jaw, with the exterior of the bone imbedded in the matrix, and its substance, for the most part, reduced to a thin layer by abrasion of the exposed inner surface (see Plate IX.). It displays accurately the contour of the fore-part of the upper jaw, which was broad, obtuse, and rounded : and some portions of the bone, with the inner surface entire, prove this part of the cranium to have been broad, flat, and of very little depth or vertical diameter. The parts preserved include the premaxillaries, 22, nasals, 15, and portions of the frontal, 11, prefrontal, 14, and maxillary, 21, bones, the proportions and connexions of which best agree with those in the skull of the Capitosaurus ,—a Labyrinthodont Batrachian, from the Bunter sandstone of Bernburg. The premaxillaries, which show some obscure traces of a symphysial suture at the median line, anterior to the nasal or naso-palatine vacuities, extend outwards, on each side, for an extent of 2½ inches, and there join the maxillaries. Traces of round alveoli for teeth, some of which are 2 lines in diameter, are visible on the alveolar border of the premaxillaries. The alveolar border is continued, by the maxillary bone, for an extent of 4½ inches beyond the premaxillaries ; and this border shows still more distinct traces of aveoli

Various forms of Cetacea have been met with in the four upper beds of the Miocene strata of the Maltese group. The discovery there of teeth of Zeuglodon by Scilla, and the abundant remains of one or more species of Dugong allied to recent forms and Balœnœ, show the prevalence of these mammals in the seas of the period. They are met with in the greatest numbers in the sand-bed and nodule-bands of the Calcareous Sandstone. In the latter situation I lately discovered a tooth which appeared to me to belong to the Halitherium , and in the sand-bed an ear-bone and caudal vertebrae of possibly the same genus. The tooth and ear-bone I have shown to Professor Owen, who has confirmed their identity with the above-named genus. The molar, possibly a penultimate, has lost one of its fangs. The crown is encased in thick shining enamel, and is 9 lines in length by 8 lines in breadth; the height of the crown is 2·6 lines. The fangs are two in number; the anterior small, the posterior large and diverging. The length of the latter is 7·5 lines. The accompanying sketch represents the crown (nat. size), which probably shows a more advanced state of wear than any figured by Cuvier. The ear-bone is entire, and measures 1·4 inch in breadth, by 9 lines in vertical diameter. The specimens referred to in this note are in the Musuem of the Geological Society.