
PBOCTSEDTNaS OP GEOLOGICAL SOCIETIES. 31 Restoration of Pteraspis. ¥T DEAB SIR,—Mr. Lankester, in referring in your last number to a paper of mine, in your November number, has given us two sketches of specimens of Pteraspis and the restoration of the test by Professor Huxley. Substantially, in the diagram of Professor Huxley, and in my second figure, we have the same elements; and with my other figures Mr. Lan­ kester does not interfere. I do not think, however, that his specimens are so decisive as lie implies they arc. In his first sketch there is no decided appearance of the central ridge or prolongation, and it appears to me, that there is a much larger portion of the test posterior to the cornua than what is to bo discovered in the restoration of Professor Huxley. In his second sketch or specimen, I cannot see any certain evidence of the cornua at all, and therefore, from it also, I cannot gather how the spine or central pro­ longation of the shield is related to them. Mr. Lankester informs your readers of first-rate specimens having been in the museums and in private collections for some years. Perhaps some of these may throw light on this point, and on other points connected with Pteraspis. Meantime, believe me, my dear Sir, Yours truly, Craig, Dec. 8. HUGH MITCHELL. PROCEEDINGS OF GEOLOGICAL SOCIETIES. GEOLOGICAL SOCIETY.—November VJth.—" On the Cambrian and Huro- nian Formations, with remarks on the Laurentian." By J. J. Bigsby, M.D. The author came to the conclusion that the Cambrian and the Huronian are distinct formations, and the latter is very much tne older. December Zrd, 1862.—1. "Description of the llemains of a new Enalio- saurian (Eosaurus Acadianus), from the Coal Formation of Nova Scotia." By O. C. Marsh, Esq., NLA. Communicated by Sir C. Lyell, V.P.G.S. 2. " Description of Anthracosaurus, a new genus of Carboniferous Laby- rinthodonts." By Professor T. II. Huxley, F.B.S., F.G.S. Anthracosaurus is distinguished from all other known Labyrinthodonts by the quadrate form and oblique position of the orbits, by the existence of elongated supratcmporal foramina, and by the comparatively small number and large size of the teeth. The skull exhibited had an extreme length of 15 inches, and an extreme width of 12 inches. There are about 30 maxillary, 2 vomerine, and 10 palatine teeth, which are ridged, and be­ come flattened and two-edged towards their apices. The vomerine, pala­ tine, and some of the anterior maxillary teeth are between 2 and 3 inches long, and from \ to f of an inch in diameter at the base. The species ex­ hibited was named A. liusselli, after its discoverer. Probably its entire skeleton had a length of not less than 6 feet. 3. " On the thickness of the Pampean Formation near Buenos Ayres." By Charles Darwin, Esq., M.A., F.E.S., F.G.S. Some sections of Artesian wells sunk in this formation showed its entire thickness near Buenos Ayres to be about 210 feet. It was stated to rest upon various marine beds upwards of 100 feet thick, containing Ostrea Patagonira, Ostrea Alvarezii, Pecten Paranensis, etc. These reposed upon red calcareous clay, which was bored through to a depth of 213 feet more, contained no fossils, and is of unknown age. 82 THE GEOLOGIST. 4. " Geological Notes on the Locality in Siberia where Fossil Fishes and Bstherise wrere found by Dr. Middendorf." By C. E. Austin, Esq., C.E., F.G.S. 5. "Note on Estheria Middendorfii." By Professor T. "Rupert Jones, F.G.S. Two ancient stone axes from Trinidad, and one from Santa Cruz, were exhibited by J. Lamont, Esq., F.G.S. December 17th.—1. "On the Skiddaw Slate Series." By Professor R. Harkness; with a note on the Graptolites, by Mr. J. W. Salter. Some general sections through the Skiddaw Slates were described in detail, and the localities in which fossils had been previously found by Professor Sedgwick were especially noticed. The author stated that he had discovered several species of Graptolites new to the Skiddaw Slates in certain flaggy beds almost devoid of cleavage, which occur at intervals in the lower portion of the series, in several localities. Professor Harkness showed that these rocks were much more fossiliferous than had hitherto been supposed; and that the evidence of the fossils, as interpreted by Mr. Salter, clearly proved them to be of the same age as the Lower Llandeilo rocks of Wales and the Quebec Group of Canada. The thick­ ness of the Skiddaw Slates was estimated at 7000 feet, and the total thick­ ness from the base of the Skiddaw Slates to the Coniston limestone at 14,000 feet. Besides several species of well-known Graptolites that are also found in the Lower Llandeilo rocks and in the Quebec Group (Taconic System), Mr. Salter has been enabled to identify Phyllograpsus angustifolium, Hall, Tetragrapsus bryonoides, Hall, and another species of that genus, Dichograpsus SedgwicTci, n. sp., Didymograpsus caduceus, and some others. He has given the name of Caryocaris Wrightii to a Crus­ tacean discovered in these rocks by Mr. Wright. Mr. Salter considers the Skiddaw Slates to be of the same ago as the Quebec Group, the graptolitiferous rocks of Melbourne, and the Tremadoc Slates of Wales. 2. " On Fossil Estherice, and their Distribution." By Professor T. Rupert Jones. The author pointed out the chief characters of the fourteen species of Estherice obtained, from several geological formations; and stated that they belong mainly to the passage-beds, and he believed chiefly to fresh and brackish waters. He also compared the distribution of the twenty-two recent species with that of the fossil Estlieri.ce. 3. " On the Flora of the Devonian Period in North-Eastern America." By Dr. J. W. Dawson. Dr. Dawson enumerated in this Appendix some additional species of plants lately obtained from Perry, by Mr. Brown, of that place. He also stated that recent observations have shown that the beds spoken of in his paper as belonging to the Cattskill Group of New York, really represent the Chemung Group of that State, according to Professor J. Hall. ROYAL SOCIETY.—November 20th.—One of the largest meetings of the Royal Society we remember to have seen. The attraction was Professor Owen's paper on the remarkable fossil feathered animal which has lately been added to the national collection—the Archceopteryx macrurus. In his opening remarks Professor Owen detailed the circumstances attend­ ing the discovery of the first evidence of the class Birds in the Oxfordian strata, being the impression of a feather, which was described by Hermann von Meyer, who established for it the genus Archaiopteryx. This name was retained for the present feathered animal. On November 9, 1861, Andreas Wagner communicated to the Mathematical and Physical Aca­ demy of Munich the account of the discovery of an animal with divergent fans of feathers, with which he had become acquainted, on the authority of PBOCEEDIN'GS OF GEOLOGICAL SOCIETIES. 33 M. Witte. Warner termed this animal Griphosaurus, and, unfortunately, soon after died. Professor Owen communicated with the owner, M. Ha- berlein, of Pappeiilieira, whose collection Mr. Waterhouse was deputed to inspect, and ultimately to purchase. The ventral aspect of the specimen was exposed, the furculum marking the fore part of the trunk. It was 1 foot 8| inches in length, and measured across, from the apex of the right so the left wing, 1 foot 4 inches. ]N'ear the anterior border of the impres- tions of the wings the stone was broken. The head may have been within this broken part. The ischium, showing the acetabulum, twenty caudal vertebra;, several ribs, the left scapula, proximal part of the left humerus, distal part of ditto, left radius, ulna, and carpals, right humerus, radius, and ulna, two right metacarpals, and two ungual phalanges, right femur, right tibia, left femur, left tibia, were preserved, as well as impressions of the quill feathers, and of down on the body; one clawbone belong­ ing to the right digit of the wing was present, of which bone counter­ part impressions exist. The vanes, and even the shafts of the feathers, can be distinctly seen by the naked eye. The furculum, pelvis, and bones of the tail are in their natural positions. The left scapula is displaced back­ wards : the left humerus outwards and a little forwards, as well as the antibrachium. The wing feathers diverge one inch in front of the carpus. The right humerus extends backwards, and the two metacarpals or proxi­ mal phalangeals are dislocated inwards. Fourteen long quill-feathers di­ verge on each side of the metacarpal and phalangeal bones ; the tibia ex­ tends outwards. The foot is contracted ; the left femur is turned outwards. The feathers decrease in length from six inches to one inch ; the anterior series of barbs are longest and obtusely rounded. The area covered by the diverging quills of the left wing is 14 inches ; by the right, 11. The three posterior primaries are dislocated backwards ; one primary is exqui­ sitely preserved. The impressions of tail feathers number twenty, and succeed each other ; the principal correspond in number on each side with the tail vertebra. The length of the anterior tail feathers is 1 inch, at the end 5 inches; the tail is 11 inche3 in length, and 3j in breadth, being obtusely truncated at the end. The wings have a general resemblance to those of the gallinaceous, or round-winged birds. The scapula resembles that of a bird, and was compared with a structure in Pterodactylus Sue- •vicus, which was about the same size as Archseopteryx.
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