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Locephalina, 1 Species; Conocoryphe, 2 Species; Anol~Ole~Us, 2 Species; Cyrtotl~Eca, 1 Species; Stenotheca, 1 Species; Theca, 2 Species; Protocystites, 1 Species, &C

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Locephalina, 1 Species; Conocoryphe, 2 Species; Anol~Ole~Us, 2 Species; Cyrtotl~Eca, 1 Species; Stenotheca, 1 Species; Theca, 2 Species; Protocystites, 1 Species, &C Downloaded from http://jgslegacy.lyellcollection.org/ at New Mexico State University on January 17, 2016 48 PROCEEDINGS OF TITE GEOLOGICAL SOCIETY. [Dec. 6, Trilobites, I0 genera and 30 species. Bivalved and other Crustaceans, 3 genera and 4 species. Brachiopods, 4 genera and 6 species. Pteropods, 3 genera and 6 species. Sponges, 1 genus and 4 species. Cystideans, 1 genus and 1 species. By adding to these the Annelids, which are plentiful also in these rocks, we get seven great groups represented in this fauna, the earliest known at present in this country. By referring to the Tables published in ~[. Barrande's excellent new work on Trilobites, it will be seen that this country also has produced a greater variety, or, rather, representatives of a greater number of groups from these early rocks, than any other country. The species described included Agnost,.~, 5 species ; Arionellus, 1 species ; F_~nnys, 1 species ; //o- locephalina, 1 species; Conocoryphe, 2 species; Anol~ole~us, 2 species; Cyrtotl~eca, 1 species; Stenotheca, 1 species; Theca, 2 species; Protocystites, 1 species, &c. The author also entered into a consideration of the range of the genera and species in these early rocks, and showed that, with the exception of the Brachiopods, Sponges, and the smaller Crustacea, the range was very limited. A description of the various beds forming the Cambrian rocks of St. David's was also given, and proofs adduced to show that fre- quent oscillations of the sea-bottom took place at this early period, and that the barrenness of some portions of the strata and the richness of other parts were mainly attributable to these frequent changes. DISCUSSION. Mr. GwrN JEFFI~EYS suggested that the term Polyzoa might be adopted in preference to that of Bryozoa, as being the more ancient term, and that the name Proserpina should not be applied to the new genus of Trilobites, as it had already been appropriated to a tropical form of land-shell. Mr. HIcxs thanked Mr. Jeffreys for his suggestions, which he was inclined to adopt. DECEMBER 20, 1871. Frederick tt. Bowman, Esq., F.R.A.S., F.C.S., of Halifax, York- shire, and Thomas Charles Sorby, Esq., F.R.I.B.A., of 27 Bruns- wick Square, W.C., were elected Fellows of the Society. The following communications were read :-- 1. A letter from G. MIT.~ER STEPR~, Esq., F.G.S., to the late Sir ROD~RICX Mv~cnIsO~, dated Sydney, 5 October, 1871, from which the following is an extract :-- "As I regard yourself as the ~rophet of gold-discovery in Aus- tralia &c., I cannot refuse myself the pleasure of asking you to be- come the medium of my communicating to the Geological Society of London two very interesting discoveries recently made in this hemi- sphere. Downloaded from http://jgslegacy.lyellcollection.org/ at New Mexico State University on January 17, 2016 1871.] s~sem~--~Ew GOT.D- A~D Tr~-D~.eosi~s. 43 "1. That of gold on the banks of the River Bondg on the N.E. coast of New Caledonia. It was discovered by a party of four men (two being Australian miners), in consequence of a splendid reward offered by the French Government in the island for the discovery of a gold-field. The head of the party brought up to Sydney about 2~ tons of auriferous drift which was highly charged with very fine, almost invisible, gold-dust; and having seen my two patent machines he offered me one-fifth of their grant of 500 hectares for a 'plant' of the machines and steam- engine. Accordingly I accepted the offer, having ascertained from the Master of the Mint that the auriferous drift contained about 16 oz. to the ton ! And my son, who is now in the island watching over our interests, finds my expectations quite confirmed, and predicts a fortune and the near proximity of a quartz ' reef,' having recently found a small quartz-boulder studded with coarse gold. " I shall be much surprised if they do not shortly find the ordinary quartz-veins, and of great richness, as the micaceous sandstone containing three fourths of the gold they are getting at present bears evidences of being the d~bris and sedimentary deposit of rich gold- bearing rocks. " No. 2 discovery is the very recent one of what I believe to be an enormous deposit of tin-ore, in pepitas, crystals, and beds of con- glomerate, and especially in micaceous granite, more or less decom- posed. Small specimens I send you herewith by a Sydney merchant (Mr. Ed. Chapman), who proceeds 'over land' from India, and can only burthen himself with a tiny parcel. I promise myself the gra- tification of sending to the Geological Society some large specimens by the first eligible opportunity. "The centre of this deposit (which extends at least some miles) is about 29 ~ 40' S. latitude and 151 ~ 20' E. longitude, being in the district of New England, and about 15 miles E. from the township of Inverell on the borders of the Macintyre River. The country is granitic, with whinstone. "I had long ago heard from a correspondent of this tin-deposit having been discovered by a shepherd, but did not believe it was of such prodigious value as I now know it to be. I shall probably visit the locality shortly, and will then give a more detailed account of a discovery which I believe will sensibly affect the markets of the world, as regards this most useful metal. "By assay the ' peroxide ' proves to be very rich in metal, about 75 per cent." ~)ISCUSSION. Mr. D. FORBES stated that in 1859 he had p]aced in his hands some specimens of granite from the district the discovery of tin in which was announced by Mr. Stephen, and that he found them to be per- fectly identical with the stanniferous granites of Cornwall, Spain, Portugal, Bolivia, Peru, and Malacca, which he had also examined. These granites were all composed of white orthoclase felspar, colourless or black Muscovite mica, and quartz. He was not aware that tinstone (cassiterite or oxide of tin) occurred anywhere in Downloaded from http://jgslegacy.lyellcollection.org/ at New Mexico State University on January 17, 2016 44 PRO~GS OF ~ axO~OOICAT, so~rrT. [Dee. 20, rock of a different character. It was always accompanied by more or less native gold. Mr. PATTXSO~ remarked that in many places where tin occurred it was not present in sufficient quantity to be remuneratively worked. Mr. D. FORBES,in answer to a question from Prof. Ramsay, stated that, as far as could be ascertained, the age of the stanniferous granites mentioned by him must be between the end of the Silurian and the early part of the Carboniferous period. Prof. RAMSAYWould carry them down to the close of the Carbo- niferous period, and would be contented to term them pre-Permian.. 2. REMXEXS On ~ G~AND ]~Et"rzs. By Professor A. E. No~E~s~Sw, For. Cot. G. S. THE meteorites which I discovered at Ofivak, in Greenland, in 1870, most of which have now been brought home by the expedition of this year under the command of Baron v. Otter, seem to have formed the principal masses of an enormous meteoric fall, which took place during the Miocene period, extending over an im- mense area (some 200 English miles) not only of the region occupied by the (~reenland basalt, but also where the country is composed of granite-gneiss. The native iron is very variable in appearace ; but as far as I yet can judge, it is free from silicates, notwithstanding that pieces of basalt (apparently ?) are imbedded in the exterior of the blocks, apparently filling cavities in the outer surface of the original me- teorites. The basalt at a distance from this locali~ does not contain any native iron; it is only in the immediate vicinity of the iron masses themselves that native iron along with pebbles is fbund in the basalt, which at this place is clearly seen to be a subsequently con- solidated basalt-tuff and not congealed lava. That this iron is of eruptive origin appears impossible to me, because :--(1) the iron, upon being heated, evolves gaseous matter even up to as much as 100 times the volume of the iron itself; (2) it contains distinct isolated particles of sulphide of iron, which are imbedded in the rest of the mass of iron, which in itself is free or nearly free from sulphur ; (3) the external form of the iron masses themselves does not show evidences of their having been poured out, when in the molten condition, into a cavity or fissure. The character of the iron masses is extremely variable, as they are in part composed of meteoric niekeliferous cast iron, or of meteoric nickeliferous wrought iron, or mixtures of both ; in which last case the so-called Widmannst~etten's figures are found to be best developed. The native iron found in the basalt occurs :m A. As enclosed and but little altered meteoric stones. B. Filling up cracks from one to two lines in width, and being either fragments of meteorites flattened out under the influence of time, or wedged into these cracks in the act of falling, or which have, fallcn into cracks in the subsequently consolidated tuff. .
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