Reports and Proceedings — Geological Society of London. 321 



Geological Society of London. 

 L— May 21, 1890.— Dr. A. Geikie, F.R.S., President, in the 

 Chair. — The following communications were read : — 



1. "On some Devonian and Silurian Ostracoda from North 

 America, France, and the Bosphorus. By Prof. T. Rupert Jones, 

 F.R.S., F.G.S. 



Of the Devonian species herein figured and described, six species 

 and one variety (four being new) from the decomposed Chert of 

 the Corniferous Limestone of Ontario County, in the State of New 

 York, and new species from the Hamilton Group of Clarke Co., 

 Indiana, have been sent by Mr. J. M. Clarke, of Albany, N.Y., as 

 mentioned in the February number of the Quart. Journ. Geol. Soc. 

 p. 14. From Eighteen-mile Creek, Lake Erie, N.Y., there are two 

 new Devonian species among specimens supplied by Dr. Hinde (op. 

 cit. p. 28), and two new Primitice from Thedford. Altogether five 

 genera (Bollia, J. & H., Moorea, J. & K., Octonaria, J., Eurychilina, 

 Ulrich, and Ulrichia, gen. nov.) are hereby added to the list of 

 " Hamilton " fossils. 



The Devonian Beyrichia collected some years ago by M. Dumont 

 at the Bosphorus, and noticed by Dr. Ferd. Romer in the 'Neues 

 Jahrbuch ' for 1863, having been kindly lent by M. Dewalque for 

 examination, is figured and described in detail. It appears to be 

 the same as B. devonica. Jones, lately described from Devonshire. 



Nine new species from Anticosti, in Dr. Hinde's collection, alluded 

 to above, are here figured and described. They are from Mr. 

 Billings's "Anticosti Group" (Divisions 3, 2, 1, and the lowest). 

 The lowest and Div. 1 are both now regarded as of Lower Silurian 

 age, and Divs. 2 and 3 are either Middle or Upper Silurian. A 

 series of Silurian Ostracoda from Canada, submitted by Mr. 

 Whiteaves, F.G.S., and Mr. Ami, F.G.S. , have been examined, and 

 critical notes on them are here given. 



The Lower-Silurian Beyrichia Gailleri, named and compared with 

 other species by M. G. de Tromelin at Nantes in 1875, who found 

 it at Dom front and elsewhere in Brittany, is also figured and 

 described in detail. 



2. "On the Age, Composition, and Structure of the Plateau- 

 gravels of East Berkshire and West Surrey." By the Rev. A. 

 Irving, B.A., D.Sc, F.G.S. 



The author refers to the view propounded by him somewhat 

 tentatively seven years ago, and since confirmed by the researches 

 of Prof. Prestwich, as to the Preglacial age (probably Pliocene) of 

 these deposits, pointing out the inconclusive nature of the evidence 

 of Glacial age furnished by the presence in them of angular 

 " sarsens." He regards the absence of Miocene marine deposits in 

 this part of North-western Europe as supporting the published view 

 of Zittel and other continental writers that the Miocene period was, in 

 South-eastern England, one of elevation and subaerial waste and 



