which are imbedded by single fangs, and apparently lodged in distinct alveoli. The summit of the crown, when unworn, is sharp and presents no trace of the serrations characteristic of Iguanodon; but it is sinuated by the terminations of the strong ridges of enamel which traverse the outer surface of the crown. The teeth thus present some resemblance to those of Iguanodon; but the author regarded the two forms as perfectly distinct, and named the species under consideration Hypsilophodon Foxii. Of the lower jaw the right ramus is present; but its distal extremity is broken off, and its teeth are concealed. On the outer surface of the lower jaw the centrum of a vertebra is preserved. The author then referred to a fossil skeleton in the British Museum, which has been regarded as that of a young Iguanodon; it is from the same bed as the skull previously described. The author remarked that, in form and proportions, the vertebræ were quite different from those of Iguanodon, and apparently identical with those of his new genus, as shown by the centrum preserved with the skull: the animal had at least four well-developed toes; and other peculiarities were indicated, which seem to prove that it was quite distinct from Iguanodon. This skeleton the author identified with his Hypsilophodon Foxii, and described its characters in detail, dwelling especially upon the peculiarities of the pelvic bones, which are singularly avian in their structure. 4. "Further Evidence of the Affinity between the Dinosaurian Reptiles and Birds." By Professor Huxley, F.R.S., President. In this paper the author reviewed the evidence already cited by himself and others (especially Professor E. D. Cope) in favour of the ornithic affinities presented by the Dinosauria, and discussed at length the recently ascertained facts which bear upon this question, some of the most important of which are derived from the species described by him in the preceding paper under the name of Hypsilophodon Foxii. He summed up his paper by a comparison of the different elements of the pelvic arch and hind limb in the ordinary reptiles, the Dinosauria and Birds, and maintained that the structure of the pelvic bones (especially the form and arrangement of the ischium and pubis), the relation between the distal ends of the tibia and the astragalus (which is perfectly ornithic), and the strong cnemial crest of the tibia and the direction of its twist furnish additional and important evidence of the affinities between the Dinosauria and Birds. Mr. SEELEY doubted whether these animals should be called Reptiles at all, as they seemed to him to form a group distinct alike from reptiles, birds, and mammals, but occupying an intermediate position. In the hinder limbs of Pterodactylus the analogies were closer with mammals than with birds. He thought it possible that the peculiar structure of the hinder limbs of the Dinosauria was due to the functions they performed rather than to any actual affinity with birds. The PRESIDENT, in reply, stated that Hypsilophodon, from the character of its teeth, probably subsisted on hard vegetable food. He expressed a hope that Mr. Fox would allow a closer examination of his specimens to be made. He was unable to agree with Mr. Seeley's views. He was inclined to think that the progress of knowledge tended rather to break down the lines of demarcation between groups supposed to be distinct than to authorize the creation of fresh divisions. November 24th, 1869.-Prof. T. H. Huxley, LL.D., F.R.S., The following communications were read: 1. "On the Dinosauria of the Trias, with observations on the Classification of the Dinosauria." By Prof. Huxley, LL.D., F.R.S., President. The author commenced by referring to the bibliographical history of the Dinosauria, which were first recognized as a distinct group by Hermann von Meyer in 1830. He then indicated the general characters of the group, which he proposed to divide into three families, viz.: I. The MEGALOSAURIDE, with the genera Teratosaurus, Palæosaurus, Megalosaurus, Poikilopleuron, Lalaps, and probably Euskelo saurus; II. The SCELIDOSAURIDE, with the genera Thecodontosaurus, Hylæosaurus, Pholacanthus, and Acanthopholis; and III. The IGUANODONTIDE, with the genera Cetiosaurus, Iguanodon, Hypsilophodon, Hadrosaurus, and probably Stenopelys. Compsognathus was said to have many points of affinity with the Dinosauria, especially in the ornithic character of its hind limbs, but at the same time to differ from them in several important particulars. Hence the author proposed to regard Compsognathus as the representative of a group (Compsognatha) equivalent to the true Dinosauria, and forming, with them, an order to which he gave the name of ORNITHOSCELIDA. The author then treated of the relations of the Ornithoscelida to other Reptiles. He indicated certain peculiarities in the structure of the vertebræ which serve to characterize four great groups of Reptiles, and showed that his Ornithoscelida belong to a group in which, as in existing Crocodiles, the thoracic vertebræ have distinct capitular and tubercular processes springing from the arch of the vertebra. This group was said to include also the Crocodilia, the Anomodontia, and the Pterosauria, to the second of which the author was inclined to approximate the Ornithoscelida. As a near ally of these reptiles, the author cited the Permian Parasaurus, the structure of which he discussed, and stated that it seemed to be a terrestrial reptile leading back to some older and less specialized reptilian form. With regard to the relation of the Ornithoscelida to birds, the author stated that he knew of no character by which the structure of birds as a class differs from that of reptiles which is not foreshadowed in the Ornithoscelida, and he briefly discussed the question of the relationship of Pterodactyles to birds. He did not consider that the majority of the Dinosauria stood so habitually upon their hind feet as to account for the resemblance of the hind limbs to those of birds by simple similarity of function. ; The author then proceeded to notice the Dinosauria of the Trias, commencing with an historical account of our knowledge of the occurrence of such reptilian forms in beds of that age. He identified the following Triassic reptilian forms as belonging to the Dinosauria :--Teratosaurus, Plateosaurus, and Zanclodon from the German Trias Thecodontosaurus and Palæosaurus from the Bristol conglomerate (the second of these genera he restricted to P. cylindrodon of Riley and Stutchbury, their P. platyodon being referred to Thecodontosaurus); Cladyodon from Warwickshire; Deuterosaurus from the Ural; Ankistrodon from Central India; Clepsysaurus and Bathygnathus from North America; and probably the South-African Prote rosaurus. 2. "The Physical Geography of Western Europe during the Mesozoic and Cainozoic periods, elucidated by their Coral-faunas." By P. Martin Duncan, M.B. Lond., F.R.S., Secretary. The author commenced with a notice of the typical species of the coral-fauna of the deep seas which bound continents remote from coral-reefs, and then made some remarks upon the littoral corals. The peculiarities of reef, lagoon, and shallow-water species were then explained, with the relations of the two faunas to one another. The author then referred to certain exceptional species, indicated the genera the species of which constitute the existing reefs and contributed to form those of the past, and noticed the representatives of some modern genera in old reefs. He pointed out that a correspondency of physical conditions during the deposition of certain strata was indicated by their containing analogous forms-the presence of compound cœnenchymal species indicating neighbouring reefs, and their absence in places where simple or non-coenenchymal Madreporaria are found being characteristic of deep-sea areas remote from the Coral-seas. By applying the principles thus elaborated to the evidence as to the condition of the seas of the European area from the Triassic period to the present time, the author then showed what must probably have been the physical condition of this part of the world at different periods. December 8th, 1869.-Prof. T. H. Huxley, LL.D., F.R.S., The following communications were read :— 1. "Notes on the Brachiopoda hitherto obtained from the Pebblebed at Budleigh-Salterton, near Exmouth, in Devonshire." By Thomas Davidson, Esq., F.R.S., F.G.S., &c. The author first described the general characters, and discussed the opinions that have been put forward as to the origin, of the pebbles forming this bed. Nearly 40 species of Brachiopoda have been obtained from them. The fossils contained in the pebbles have been regarded as of Lower-Silurian age; the author considered the great majority of the Brachiopoda to be Devonian. The species identified with Silurian fossils are:-Lingula Lesueuri (Rouault), L. Rouaulti (Salter), and L. Hawkei (Rouault). The species regarded by the author as undoubtedly Devonian (i. e. either previously described from Devonian deposits or associated with such species in the same pebble) are 12 in number, namely:-Spirifer Verneuilii (Murch.), S. macroptera (Goldf.), Athyris budleighensis (sp. n.), Atrypa (reticularis?), Rhynchonella inaurita (Sandb.), R. elliptica (Schnurr), R. Vicaryi (sp. n.), and 2 undetermined species of Rhynchonella, Streptorhynchus crenistria (Phil.), Productus Vicaryi (Salt.), and an undetermined Chonetes. Eight species occurring in the same rock, three of which have been doubtfully identified, are considered by the author to be probably Devonian. The species supposed to be determined are:-Orthis redux (Barr.) and 0. Berthosi (Rouault), Silurian; and Spirifer octoplicatus (Sow.), Devonian and Carboniferous, but possibly identical with the Silurian S. elevatus (Dalm.). The others are 2 new species of Orthis, and a new Rhynchonella (?), and an undetermined species of Terebratula (?) and Strophomena (?). Finally the author noticed 14 species (all new, except Orthis pulvinata, Salt.) only known from these pebbles, but which were stated to possess a Devonian facies. 2. "On the relation of the Boulder-clay without Chalk of the North of England to the Great Chalky Boulder-clay of the South." By Searles V. Wood, Jun., Esq., F.G.S. The author described the Yorkshire glacial clays as of two kinds:the lower, containing chalk débris, and belonging to the uppermost member of the glacial series in Eastern and East-central England; the upper, containing chalk sparingly in its lower part, and gradually losing this upwards. On the coast only the latter occurs north of Flambro'. He stated that, paleontologically, the Lower and Middle glacial deposits closely agree with the Crag, and are quite distinct from the deposit at Bridlington, which he placed immediately above the "Great Chalky Clay.". The absence of chalk débris in the deposit north of Flambro' has been regarded as evidence of a drift from north to south; but the author stated that the purple clay without chalk extends over much of the north-eastern part of the Wolds, from the sea-level to an elevation of 450 feet, and that outliers of it occur at intervals along the Holderness coast-section as far as Dimlington, 42 miles south of the northern limit of the Wolds. In the direction of Flambro' and York the clay was said to be destitute of chalk, which would not be the case had the Wolds formed a sea-shore causing a drift from the north to pass either to south-cast or south-west. The author described the characters of the Great Chalky Boulderclay in the castern and central counties of England, and maintained On the Iron-ores and the Basalts of the North-east of Ireland. 73 that the chalk found in it (equal, according to him, to a layer of at least 200 feet over the entire Wold) could only have been detached by the agency of moving ice, which he believed to have covered nearly the whole Wold for a long period. The author stated that boulders of Shap Fell granite are confined to the deposit of clay without chalk, and discussed the means by which they could have been distributed. He ascribed their dispersion to the agency of floating ice during an adequate submergence of the district. He supposed them to have passed from Shap Fell by what is now the pass of Stainmoor. Thus he ascribed the formation of the "Great Chalky Clay" to the extrusion from the sea-foot of a great sheet of ice, of materials abraded by the latter, the land being depressed 600-700 feet below its present level; and that of the clay without chalk and with boulders of Shap-Fell granite to deposition during a period of much greater depression (about 1500 feet), throughout which the sea bore much floating ice. He considered that the "Great Chalky Clay" indicated a long period during which the land, with its enveloping ice, remained stationary, and that during this period, when intense cold prevailed, the arctic fauna of Bridlington became established. He thought that the recommencement of subsidence was indicated by the reddish-brown or brownish-purple sediments of Holderness, in which some chalk occurs. He then indicated the species of Mollusca which have occurred in the purple clay without chalk about Scarbro' and Whitby, all of which were said to belong to existing forms, and thus to be in accordance with the date assigned by him to that deposit. The molluscan fauna of Moël Tryfane was referred to by the author, who stated that he regarded it as belonging to the period of emergence from the deepest depression, during which the clay without chalk was assumed to have been deposited, i. e. to the earliest part of the postglacial period, to which the stratified drifts of Scotland are referred by Mr. A. Geikie. December 22, 1869.-Professor Huxley, LL.D., F.R.S., The following communications were read :— 1. "On the Iron-ores associated with the Basalts of the Northeast of Ireland." By Ralph Tate, Esq., Assoc. Linn. Soc., F.G.S., and John S. Holden, M.D., F.G.S. The authors introduced their account of the iron-ores of the Antrim basalts by stating that since 1790 an iron band had been known in the midst of the basalt of the Giant's Causeway, but that only within the last few years have further discoveries been made, which have developed a new branch of industry in the north-east of Ireland. The iron-ore of the numerous exposures was considered to represent portions of one sheet extending uniformly throughout the basalt and over a very large area. Indeed everywhere the iron band and |