July 23, 1874] 



NATURE 



237 



to the bones of other animals, by Harry Govier Seeley, F. L. S. 



In this paper tbe author endeavoured to give precision to the term 

 ichthyosaurian by analysing tlie characters ol the Ichthyosaurian 

 skeleton into the resemblances which it presents to skeletons of 

 •other vertebrates. Ichthyosaurian characters are subdivided into 

 Mammalian, Avian, Crocodilian, Clielonian, Lacertilian, Came- 

 lonian, Rhynchocephalian, Ophidian, Urudelan, Piscine, Plesio- 

 saurian, Dinosaurian, Dicynodont, and Labyrinthodont. By 

 thus classifying the characters it is anticipated that the affinities 

 of the IchOiyosaurian type n ay be rendered evident. — The resem- 

 blances of Pleiosaurian bones with the bones of other animals, 

 by Harry Govier Seeley, P'.L.S. This paper is an attempt to 

 make a similar analysis of the Plesiosauiian skeleton. — On the 

 tibia of Mc^alornis, a large struthious bird from the London 

 clay, by Harry Govier Seeley, F.L.S. The author con- 

 sidered that the skull named by Prof. Owen Dasoniis 

 might, if it belonged to a bird, be referred to Megahniis ; 

 but he detailed considerations which led him to suggest that 

 Dasoniis may possibly be a fish. — On cervical and dorsal 

 vertebrae of Ciocodihis canlabrigictisis .Seeley, from the Cam- 

 bridge Upper Greensand, by Harry Govier Seeley, F.L.S. — On 

 the base of a large Lacertian skull from the Potton sands, by Harry 

 Govier Seeley.F.L.S. This specimen was interpreted bythe author 

 as the anchylosed basioccipital and basisphenoid of a Dinosaur. 

 The author did not regard the specimen as giving support to 

 Prof. Huxley's hypothesis of the Avian affinities of Dinosaurs. — 

 A section through the Devonian strata of West Somerset, by 

 Harry Govier Seeley, F.L.S. — On the pectoral arch and fore 

 limb of Ophtlialiiiosmirus, by Harry Govier Seeley, F.L.S. 

 After some remarks on the structure of the pectoral arch in Ich- 

 thyosamus the author described parts of a skeleton discovered 

 by Mr. Leeds in the Oxford clay, on which he founded the genus 

 Ophlhabnosaiirus. — The glacial phenomena of the Eden Valley 

 and the western part of the Yorkshire Dale district, by J. G. 

 Goodchild ; communicated by H. VV. Bristow, F. R.S. This 

 paper is a continuation, in a northward direction, of the investi- 

 gation of glacial phenomena which formed the matter of 

 a paper lately read liefore the Society by Mr. Tiddeman, 

 and published in the Society's journal. — Geological observa- 

 tions made on a visit to the Chaderkul, Thian Shan range, 

 by the late Dr. P'. Stoliczka. In this paper the author gives 

 an account of the geology of the district traversed by him in his 

 journey from near Kashgar to Lake Chaderkul on the Russian 

 frontier, a distance of about 112 miles, his route lying among the 

 southern branches of the Thiarr .Shan Range. Three principal 

 ridges were crossed. The first, or '* Artush ridge," consisted of 

 newer Tertiary deposits of bedded clay and sand, mostly oi a 

 yellowish white colour. These " Artush beds " were traced by 

 the author for a distance of 22 miles. The southern slopes of this 

 range were covered with gravel from 10 to 15 ft. thick, which 

 passes into a conglomerate with a thickness of about 2CO ft. The 

 second, or " Kokan range," is formed on the southern side of 

 old sedimentary rocks, whilst the northern is occupied by newer 

 Tertiary deposits and basaltic rocks, the former consisting of 

 shales and limestones, in whiclr the author found some fossils, 

 inducing him to refer them to the Trias. These are .succeeded 

 by some d.irk-coloured shales, .slates, and sandstones, dipping at 

 a high angle to the north. On the denuded edges of these the 

 new Tertiaries rest, consisting of sandstones interstratified with 

 basaltic rocks. These latter increase in thickness till just beyond 

 Kuija an old " somma " is reached, with perpendicidar walls 

 rising to a height of 1,500 ft. above the river. Tire cone of the 

 volcano has disappeared by subsidence. The third ridge, " Te- 

 rek-tagh," consists of old sedimentary rocks, chiefly limestones. 

 — Note upon a recent discovery of tin-ore in Tasmania, by 

 Charles Gould. — Note on the occurrence of a Labyrinthodont 

 in the Voredale rocks of Wensleydale, by L. C. Miall ; 

 communicated by Prof. Huxley, F.R.S. The author briefly 

 describes a specimen, discovered by Mr. W. Home, of Leyburn, 

 in the Lower Carboniferous Rocks there, comprising casts of five 

 bones. He considers that" these bones belong to .an .an'm.al 

 of higher rank than any known fish, and thinks that the Lower 

 Coal-meamres of Glasgow, with Zd.vdotwi/, maybeof earlier date 

 than the Yoredale Rocks. — Geological Notes on the route tra- 

 versed by the V.arkund Embassy from Shahidulla toYarkundand 

 Kashgar, by Dr. F. Stolickza. The author described the rocks 

 observed by him along the course of the Karakash river and 

 through the Sanju pass as chiefly metaniorphic, and very highly 

 inclined, until near Y.im sedimentary rocks rest unconformably 

 on the schists. These are probably l'ala.'ozoic. Later rocks 



occur near the camp ICiw,iz, some resembling the rocks of 

 the Nahi'in group, and underlain by deposits containing Car- 

 boniferous fossils. At Sanju coarse grey calcareous sand- 

 stones and chloritic marls of Cretaceous age occur. True Loss 

 occurs in some of the valleys.— The hematic deposits of White- 

 haven and Furness, by J. D. Kendall.— Notes on the Physical 

 Characters and Mineralogy of Newfoundland, by John Milne. 

 Notes on the Sinailic Peninsula and north-western Arabia, by 

 John Milne.— Giants' Kettles at Christiania, by MM. W.' C. 

 Brogger and II. H. Reusch ; communicated by Prof. Kjerulf. 

 The authors first refer to the popular notices about giants' 

 kettles, and describe in detail a number of these pits, which 

 were examined and emptied near Christiania. They then 

 mention the theory concerning their origin. From their own 

 facts and reading they conclude that many of these remarkable 

 pits were made at the bottom of " Moulins " during a glacial 

 period, when the locality was covered with ice on the scale of 

 existing ice in Greenland. The contents of these pits are traced 

 to their parent rocks, which are higher up towards the great 

 valley of Gulbransdal, in which glacial phenomena abound. 

 They are inclined to conclude that moraine matter was washed 

 off the glacier-ice from time to time, and left in the pits at last. 



Geologists' Association, July 3. — Henry Woodward, F. R. S. 

 president, in the chair.— On the deposits now forming in British 

 seas, by G. A. Lebour, F.G. S. The author limited his present task 

 to a brief description of the principal constituents of British sea- 

 bottoms, with particular reference to their distribution and its 

 causes. The materials are of mechanical, chemical, or organic 

 origin. — Roc/;-bottoins. In some places no deposit occurs, the bare 

 rock being left. The largest ot these bare spots, in British seas, 

 occurs in the western half of the Channel Valley. Their distri- 

 bution is directly connected with that of currents, and this is 

 strikingly proved by their being limited to no rela'ive depth ; 

 for, in the Channel, their range extends entirely across the valley. 

 Another bare area exists at the point where the Atlantic cable 

 enters the yet deeper region of the Atlantic ooze in 500 fathoms 

 water. The specimens brought up by the sounding instruments 

 from such places consist of weathered and rotten stone, pointing 

 to chemical rather than mechanical disintegration, even where 

 powerful currents are present. — Marine deposits. These consist 

 chiefly of sand, with occasional islands of clay, mud, gravel, and 

 shell detritus. The broader the sea the greater the proportion of 

 sand : thus the North Sea bottom is especially a sandy one, though 

 towards the centre the sand becomes muddy over a considerable 

 region. Sandy bottoms also largely prevail in the north-western 

 seas and on tire west coast of Ireland ; but south of Ireland a 

 large expanse of pure mud and muddy sand extends in a south- 

 easterly direction. — Organie deposits. In the Channel the shell 

 deposits attain their greatest development as regards British 

 seas. There they form two long, occasionally broken lines, fol- 

 lowing at a short distance the English and French shores, and 

 forming at the oitter mouth of the Channel a vast shell bank. 

 These deposits actually cross the broad sea-valley partly over 

 and considerably to the west of the spread of bare rock pre- 

 viously meirtioned. Beyond the oceair valley which lies be- 

 tween the Hebrides and the Rock-hall reef, there occurs a 

 fish bank more than three miles in length, affording us an 

 inkling of the manner in which some of our long-fossilised 

 fish-beds may originally have been accumulated. — I-lui'io- 

 marine deposits. The Thames, Seine, and Tay form mud 

 banks in a sandy sea. The submarine delta of the former 

 has the shape of a triangle, of which the apex points sea- 

 wards ; that of the Seine is also triangular in outline, but the 

 apex points landwards. .Such submarine deltas can only 

 be recognised when the materials of which they consist are 

 distinct from those forming the prevailing sea-bottom. Al- 

 though much of the above materials are at present incoherent, 

 especially the sands, it is not probable that the larger features of 

 thesea bottoms are liable to important changes, whilst the sur- 

 rounding geogrciphical conditions remain unaltered. The same 

 agencies, which sweep certain spots, have heaped-up material 

 elsewhere, and the relative form of both covered and uncovced 

 portions of the sea-floor is preserved by them. The points of 

 the greatest violence of current action are shown by the bare 

 rock patches, whilst the intermediate stages of agitation are re- 

 presented by coarse shingle, sandy gravel, sand, and finally patches 

 of mud or clay supervene, which, to a certain extent, indicate 

 centres of calm. 



Entomological Society, July 6. — Sir Sidney Smith 



