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Geological Society, December 20, 1871.-Mr. Joseph Prest-wich, F.R.S., president, in the chair. Mr. Frederick H. Bowman, F.R.A.S., F.C.S., of Halifax, Yorkshire, and Mr. Thomas Charles Sorby, B.A., F.R.S., of 27, Brunswick Square, W.C., were elected Fellows of the Society. The following communica-lions were read:-1. A Letter from Mr. G. Milner Stephen, F.G.S., to the late Sir Roderick Murchison, dated Sydney, 5th October, 1871, announcing the discovery of a rich auriferous deposit on the banks of the River Bonde, on the N.E. coast of New Caledonia, and of a great deposit of tin-ore in the district of New England, New South Wales. The gold in New Caledonia is found in drift, and there are indications of the near proximity of a quartz-reef. The tin-ore in New South Wales is said to be in "pepitas, crystals, and beds of conglomerate, especially in micaceous granite, more or less decomposed.“Mr. D. Forbes stated that in 1859 he had placed 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 perfectly 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 rock of a different character. It was always accompanied by more or less native gold. Mr. Pattison 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. R.amsay, 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. Ramsay would carry them down to the close of the Carboniferous period, and would be contented to term them pre-Per r mian.-"Remarks on the Greenland Meteorites.“By Prof. A. E. Nordenskjold, For. Corr. G.S, The author stated that the masses of meteoric iron brought from Greenland by the recent Swedish expedition seem to have formed the principal masses of an enormous meteoric fall of miocene date, extending over an area of some 200 miles. The iron appears to be free from silicates. Against its eruptive origin the author urges that when heated it evolves a great amount of gaseous matter, and that it contains imbedded particles of sulphide of iron, the mass itself being nearly free from sulphur. The masses are composed of meteoric nickeliferous cast and wrought iron, or of mixtures of the two; in the last case the Widmannstaetten's figures are best developed. The author further noticed the various modes in which the iron occurs, viz., 1, as meteorites; 2, filling cracks; 3, as brecciseform stones cemented with oxide and silicate of iron; and 4, in grains disseminated in the basalt. Mr. Roberts protested against the evolution of gaseous matter being considered as a proof of meteoric origin. Prof. Ramsay reiterated his previously-expressed opinion, that the masses of iron might be of telluric origin.-“Further Remarks on the Relationship of the Limulidce {Xiphosura) to the Eurypteridce and to the Trilobita“By Mr. Henry Woodward, F.G.S. In this paper the author described the recent investigations made by Dr. A. S. Packard, Dr. Anton Dohrn, and the Rev. Samuel Lockwood upon the developmental history of the North American King-crab {Limulus Polyphemus), and discussed the conclusions as to the alliances of the Xiphosura and Eurypteridce, and to the general classification of the Arthropoda, to which the results of these investigations have led Dr. Dohm and some other Continental naturalists. According to this view, the Xiphosura and Eurypteridce are more nearly related to certain Arachnida (the Scorpions, &c.) than to the Crustacea; and this opinion is further supported by the assertion of Dr. Dohm, that in Limulus j only one pair of organs (antennules) receives its nerves from the j supraoesophageal ganglion, and that the nature of the underlip in j Limulus differs from that prevailing among the Crustacea. Dr. Dohrn also recognises the relationship of the Merostomata to theTrilobites, as shown especially by the development of Limulus, and considers that the three forms {Limulidce, Eurypteridce, and Trilobita) should be combined in one group under the name of Gigantostraca, proposed by Haeckel, and placed besides the Crustacea. The author stated, on the authority of Prof. Owen, that Limulus really possesses two pairs of appendages which receive their nerves from the supraoesophageal ganglion; that, according to Dr. Packard, the young Limulus passes through a Nauplius-stage while in the that no argument could be founded upon the lower lip, the condition of which varied extremely in the three groups proposed to be removed from the Crustacea; and he maintained that even from the ultra-Darwinian point of view taken by Dr. Dohrn, the adoption of his proposal would be fatal to the application of the hypothesis of evolution to the class Crustacea. Prof. T. Rupert Jones remarked upon the interest attaching to the study of the Crustacea, and called attention to the absence of any indications of convergence in our present knowledge of the class. He thought that, in the present day, we must nevertheless look back to some point of convergence from which the varied forms known to us may have proceeded by evolution. Prof. Macdonald remarked that difficulties must be expected to occur in classification. He believed that all Invertebrate animals were to be regarded as turned upon their backs, as compared with Vertebrata. The cephalic plate I in Limulus he regarded as the equivalent of the palate-bone. The incisive palate was very distinct in the Crabs. The absence of one pair of antennas did not appear to be any reason for removing Limulus from the Crustacea. Dr. Murie considered that the contemplation of the multitude of young forms referred to by Mr. Woodward should serve as a warning to describers of species, and also as a check to generalisations as to the number of species occurring in various formations. He remarked that if we were at a point when the presence or absence of a single pair of nerves could be taken as distinguishing class from class, these classes must be regarded as very nearly allied. He thought that the doctrine of evolution was being pushed further than the known facts would warrant. Mr. Woodward, in replying, drew attention to the diagrams of the embryo and larva of the recent Limulus, comparing them with Limulus of the Coal-measures, Neolimuhis of the Silurian, and also with the larval stages of the Trilobites, discovered by Barrande. He pointed out the strong resemblance which the fossil forms offer to the early stages of the modern King-crab, and expressed his assent to the proposal of Dr. Dohrn to bring the Trilobita, if possible, nearer to the Merostomata. If, however, the Trilobites have true walking-legs instead of mouth-feet (gnathopodites) only, they would be more closely related to the Isopoda. He showed by a tabular view of the Arthropoda that the known range in time of the great classes is nearly the same, and therefore affords no argument for combining the Merostomata with the Arachnida; but on the contrary, he considered that the Trilobita were, with the Entomostraca, the earliest representatives of the class Crustacea, and could not therefore be removed from that class.-The following specimens were exhibited:-Specimens of Auriferous Quartz from New Caledonia, and of Tin Ore from New South Wales, exhibited by Mr. G. Milner Stephen; specimen of gold from the Thames Goldfield, New Zealand, exhibited by Prof. Tennant; specimens of Euryptertcs Scouleri and of Belimirus and Prestwichia, exhibited by the President; specimens of recent and fossil Crustacea, exhibited by Mr. H. Woodward, in illustration of his paper.
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Societies and Academies . Nature 5, 213–216 (1872). https://doi.org/10.1038/005213a0
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DOI: https://doi.org/10.1038/005213a0