Abstract
LONDON
Geological Society, Nov. 22.—The Rev. Thomas Wiltshire, M.A., in the chair. Mr. Samuel Baillie Coxon was elected a Fellow of the Society. The following communications were read:—1. “Notes on some Fossils from the Devonian Rocks of the Witzenberg Flats, Cape Colony.” By Prof. T. Rupert Jones, F.G.S. In this paper the author noticed some Devonian fossils like those of the Bokkeveld, found on Mr. Louw's farm on the Witzenberg Flats, Tulbagh. Orthoceras vittatum, Sandberger, was added to the South African list of fossils. The fossils under notice were stated by the author to help to substantiate the late Dr. Rubidge's view, that the old schists termed “Silurian” by Bain are of Devonian age, and continuous across the colony. Their presence in the Witzenberg Flats was also shown to be conclusive against the idea of coal-measures being found there. Mr. God win-Austen remarked that the presumed Devonian species of South Africa appeared not to have been completely identified with those of European origin. Although, judging from the range of European marine mollusca, some of which were found of precisely the same species both in Europe and at the Cape, there was nothing surprising in the extension of any old deposit, yet it seemed unreasonable to suppose that the whole district over which the wide-spread Devonian rocks extend could have been submerged at the same time. He traced the original foundation of the Devonian system to the late Mr. Lonsdale, who, in the fossils found in the deposits of Devonshire, thought he traced sufficient grounds for a marked discrimination between those beds and those of Carboniferous age. Mr. Austen had, however, always regarded the Devonian system as merely an older member of the Carboniferous, holding much the same relation to it as the Neocomian to the Cretaceous: and he would be glad to see it recognised, not as an independent system, but merely as the introduction of that far more important system, the Carboniferous, during the deposit of which the globe was subject to the same physiographical conditions. Mr. Etheridge did not agree with Mr. Austen as to the suppression of the name of Devonian system, and commented on its wide-spread distribution, and on the peculiar facies of its fossils, and their importance as a group. He was rather doubtful as to specific determinations arrived at from casts. Though the species of many fossils of Queensland procured by Mr. Daintree did not correspond with those of European areas, yet some of the corals were identical with those of South and North Devon, as were also the lithological characters of the containing beds. Mr. Seeley objected to any attempt to supersede the arrangements of the South African rocks in accordance with the local phenomena, by correlating them too closely with any European series. The recognition of the correspondence in forms seemed to him more to prove a similarity of conditions of life than any absolute synchronism. As to the connection between the Devonian and Carboniferous systems, he agreed with Mr. Austen in regarding the one as merely constituting the natural base of the other. 2. “On the Geology of Fernando Noronha (S. lat. 3° 50′, W. long. 32° 50′).” By Alexander Rattray, M.D. (Edin.), Surgeon R.N. Communicated by Prof. Huxley, F.R.S. The author described the general geological structure of Fernando Noronha and the smaller islands which form a group with it. The surface-rock was described as a coarse conglomerate, composed of rounded basaltic boulders and pebbles, in a hard, dark red, clayey matrix. This overlies a hard, dark, fine-grained basalt, which forms the most striking of the bluffs, cliffs, and outlying rocks. The highest peaks in the group consist of a fine-grained, light grey granite. The author remarked upon the possible relation of the geology of these islands to that of the neighbouring continent of South America, and stated that there is evidence of the islands having been elevated to some extent at a comparatively recent period. 3. “Note on some Ichthyosaurian Remains from Kimmeridge Bay, Dorset.” By Mr. J. W. Hulke, F.R.S. The author noticed some teeth found, with a portion of an Ichthyosaurian skull, in the Kimmeridge clay of Dorsetshire. The fragments of the snout were said to indicate that it was about three feet long and proportionally stout. The author indicated the character by which these teeth were distinguishable from those of various known species of Ichthyosaurus, and stated that they approached most closely to those of the Cretaceous I. campylodon. Mr. Seeley did not consider that, in the main, the teeth of Reptilia afforded any criteria for specific determination. In the Cambridge Greensand, though there were five species of Ichthyosaurus, possibly including a second genus, the teeth found were so closely similar that it would have been impossible, from them only, to identify more than one species. Mr. Boyd Dawkins recognised in the specimens exhibited by Mr. Hulke a form of tooth he had found in the Kimmeridge beds of Shotover, near Oxford, but which he had been hitherto unable to attribute to any recognised species. He could not fully agree with Mr. Seeley as to the absence of specific criteria in the teeth of Saurians, as, from his own experience, he was inclined to attribute some importance to their external sculpturing. 4. “Appendix to a ‘Note on a New and Undescribed Wealden Vertebra,’ read 9th February, 1870, and published in the Quarterly Journal for August in that year.” By Mr. J. W. Hulke, F.R.S. The author generically identified this vertebra with Ornithopsis, Seeley, Streptospondylus, Owen, and Cetiosaurus, Owen, taking the last to be typified by the large species in the Oxford Museum. He remarked that if this be the type of Cetiosaurus, C. brevis, Owen, can hardly belong to it, as the trunk vertebræ are described as being of a totally different structure. Mr. Boyd Dawkins, who had recently visited Oxford, stated that he had there examined the remains referred to. There was, however, no tooth found with them of a character to show the nature of the food on which the animal subsisted. But one of his students had lately found in the same pit that had afforded the remains, a tooth corresponding in its principal characters with those of Iguanodon, with which, therefore, the Cetiosaurus seemed to be allied, so that it was probably a vegetable feeder. Mr. J. Parker had lately procured from the Kimmeridge clay a number of Saurian remains, and among them were some vertebræ of Megalosaurus, to which were articulated others presenting distinctly the characters of Streptospondylus. He thought that probably many of the supposed Streptospon-dylian vertebrse might prove to belong to the cervical region of Dinosaurians. Mr. Seeley disputed the attribution to Cetiosaurus of the vertebrse describæ, and questioned whether the remains at Oxford might not be assigned to Streptospondylus or Ornithopsis. The depressions in the vertebræ, which might be connected with the extension of the air-cells of the lungs, did not exist in Cetiosaurus, but were to be found in Megalosaurus. As to the premaxillary tooth mentioned by Mr. Dawkins, he was uncertain whether it should be referred to what he considered as Cetiosaurus proper, or to the Oxford reptile. Mr. Hulke replied, pointing out that, since the determination of the Oxford reptile as Cetiosaurus, numerous other remains of the same species had been discovered, which had added materially to the basis of classification.—The following specimens were exhibited to the meeting:—Devonian fossils from the Witzenberg; exhibited by Professor T. R. Jones, F.G.S., in illustration of his paper. Specimens of Silver Ores from South America; exhibited by Professor Tennant, F.G.S. Fragment of the Wolf Rock, near the Land's End, and section under polarised light; exhibited by Mr. Frank Clarkson, F.G.S.
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Societies and Academies . Nature 5, 114–116 (1871). https://doi.org/10.1038/005114b0
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DOI: https://doi.org/10.1038/005114b0