Geological Society of London. 43 



country is occupied by Huronian slates like those between the lake and Thunder Bay. 

 These slates extend for an unknown distance north-west of the head of the lake, and 

 contain numerous veins, having an E.N.E. and "W.S.W. direction, conformable with 

 the strike of the beds, and some of them are auriferous. The vein-stuff is quartz, 

 containing copper pyrites ; the gold is contained in the copper pyrites, or disseminated 

 in very minute grains through the quartz. Several of these veins are being worked, 

 and their peculiarities were noticed by the author. 



Dismission. — Mr. H. Woodward mentioned that Dr. Nicholson had presented to 

 the British Museum some of the rich specimens of silver ore described in the paper. 



Mr. D. Forbes corroborated the author as to the richness of the ore. A lump 

 which had been submitted to him, weighing 295 lbs., containing no lesi than 187 lbs. 

 of silver. He called attention to the resemblance between the vein-stuff from 

 Thunder Bay and that from the Konigsberg silver mines of Norway, many specimens 

 being so much alike that it was impossible to distinguish them. 



2. " Note on the Eelations of the supposed Carboniferous Plants of Bear Island 

 with the Palaeozoic Flora of North America." By J. W. Dawson, LL.D., F.E.S., 

 F.G.S., F.Z.S. 



The author referred to Dr. Heer's paper on the Carboniferous Flora of Bear Island 

 (see Q. J. G. S., vol. xxviii., p. 161), and stated that the plants cited by Dr. Heer as 

 characteristic of his " Ursa Stage," are in part representatives of the American flora 

 belonging to what the author has called th« " Lower Carboniferous Coal-measures" 

 (Subcarboniferous of Dana). He considered that the presence of Devonian forms 

 was due either to the mixture of fossils from two distinct but contiguous beds, or to 

 the fact that in these high northern latitudes there was an actual intermixture of 

 the two floras. He dissented altogether from Dr. Heer's identification of these plants 

 with those of the Chemung group, or with those of the Middle Devonian of New 

 Brunswick. 



Discussion. — Mr. Carruthers stated that the list of the eleven Lower Carboniferous 

 plants published in Principal Dawson's '-Acadian Geology" did not contain a single 

 species found in Bear Island ; but, on the other hand, some species and several well- 

 marked forms were common to the Bear-Island deposits and the Devonians of North 

 America, and he had no doubt that Prof. Heer had in his paper rightly correlated 

 these floras. As to the age of these plant-bearing beds, found alike in Bear Island, 

 Ireland, the Vosges Mountains, Canada, and Australia, Mr. Carruthers said that it 

 was difiicult to draw any lines which would separate the Palaeozoic plants into clearly 

 marked and distinct floras ; but if the Devonian is to be retained as a system, all 

 these plant-bearing beds belonged rather to that system than to the Carboniferous. 



3. " Further Notes on Eocene Crustacea from Portsmouth." By Henry Wood- 

 ward, Esq., F.G.S., F.Z.S. 



In this paper, after referring to his former communication on Crustacea from the 

 Lower Eocene deposits at Portsmouth (Q.J.G.S., vol. xxviii., p. 90), the author gave 

 a full description of Rhachiosoma bispinosa, one of the new species described in it, 

 the materials being furnished by several fresh specimens, which show the whole 

 structure of the animal. The new points include the description of the limbs, the 

 anterior border of the carapace, the lower surface of the body in both sexes, and the 

 maxillipeds. 



The author also characterized, under the name of Litoricola, a new genus of Shore- 

 crabs allied to Grapsiis, from the same deposits. Of this genus he described two new 

 species, Z. glabra and L. dentata. 



Discussion. — Mr. Meyer gave some particulars as to the horizon from which theie 

 fossils were derived. They all came from the argillaceous sands with Dentalium, 

 mentioned in his former paper. These beds are much mottled, probably owing to 

 the burrowing of the crabs (Fal<eocori/stes). 



Mr. Woodward, in answer to inquiries, pointed out that these crustaceans were of 

 purely littoral, and not of pelagic forms ; and their feet were in a condition better 

 adapted for walking than for swimming. The long epibranchial spines in Rhachiosoma 

 formed weapons of offence, and were of much service to the pelagic forms, though 

 their retention in the littoral forms was not of easy explanation. The Litoricol<^ 

 were essentially adapted for running on land and burrowing. As an instance of the 

 disparity in the hands of crabs, he cited the common Calling crab, which had always 

 one hand greatly larger than the other. 



4. " On a new Trilobite from the Gape of Good Hope." By Henry Woodward, 

 Esq., F.G.S. 



