Geological Society. 73 tibus paucis, subrotundatis , longitrorsum minute plico-costatis, su-perrie insigniter fascid angustd atro-purpured cinctis, ultimo prope basin fasciato ; aperturd parvd, fused ; labio interno subproducto. Axis 3 lin. Hab. Straits of Malacca, in seventeen fathoms. Cab. Belcher. GEOLOGICAL SOCIETY. June 21, 1843. — The following papers were read : — 1. " Supplement to a Memoir on the Fossil species of Chimara." By Sir P. Grey Egerton, M.P., F.G.S. Since the author's former memoir was communicated to the So-ciety*, he has seen in the collection of Mr. Dixon a new and striking addition to the genus Ischyodus. The specimen is from the chalk of Southeram, and presents two dental plates only slightly dislocated from their natural juxtaposition. At first sight these would appear to be the dental armature of the lower jaw, corresponding nearly in size to the lower mandibles of Ischyodus Manteili. A closer exami-nation has satisfied Sir Philip Egerton that they are in reality the intermaxillary plates of the upper jaw of a most gigantic chimaeroid. They exceed in size the corresponding teeth of Ischyodus Townshendi, the largest species hitherto found, by one third. As compared with the intermaxillaries of that species they are broader, more compressed and less robust in antero-posterior diameter, and less hooked at the extremity. The form of the cutting edge is not truncate, as in the recent Chimtera, but prolonged to an acute angle, and bent down-wards like the upper mandible of a bird of prey. The symphysis is smooth and slightly hollowed. The thin polished investing lamina of compact dentine is seen adhering to the surface of the tooth. On the interior surface this is marked with broad transverse irregulari-ties similar to, although less distinct than, those seen in the recent Chimcera. A fragment in Mr. Dixon's collection gives evidence of having belonged to an individual of much larger size than that which furnished the specimens here described. Sir Philip Egerton proposes to name this species Ischyodus Gigas. 2. " On the occurrence of the remains of Insects in the Upper Lias of the county of Gloucester." By James Buckman, F.G.S. The remains described in this paper were discovered by Mr. Buck-man in a thin seam of argillaceous limestone in the upper lias beds at Dumbleton, a village twelve miles from Cheltenham, to which his attention had been directed by Mr. Brodie, who had suspected the existence of insect remains in the stratum. The section of Dum-bleton Hill, which is a liassic outlier, presents the following beds. ft. in. 1. Sandy debris from the oolite, about 10 2. Upper lias shale : this is traversed at twelve feet from its base by the thin bed of fissile limestone five inches in thickness 60 3. Lias marlstone, about 20 90 * See vol. xii. p. 467.
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