Geological Congress in Canada. 489 



Holland gave separate papers on the classification of the pre- 

 Cambrian in India, and Dr. J. J. Sederholm read "Some Troposals 

 concerning the Nomenclature of the Pre-Cambrian, etc.", the most 

 important of which led to a resolution passed by the Congress that 

 countries which possess contiguous areas of pre-Cambrian rocks 

 should form international committees, including representatives of 

 their Geological Surveys, for the purpose of correlating their pre- 

 Cambrian formations. 



The sixth topic of discussion was "To what extent was the Ice 

 Age broken by Interglacial Periods ? " Mr. G. W. Lamplugh opened 

 the discussion with a paper on "The Interglacial Problem in the 

 British Isles ". [This subject was dealt with in detail in his address 

 to the Geological Section of the British Association at York in 1906.] 

 He now stated that his views " have not been modified since in any 

 essential particular", nor could he see any "reason for supposing 

 that our Islands had been more than once enwrapped by ice-sheets, 

 however the case may stand in other countries " ; and is of opinion 

 " that the great ice-sheets held their ground in the basins 

 surrounding our Islands throughout the deposition of the drift series, 

 and that the supposed Interglacial deposits are indicative only of 

 marginal fluctuations and of the independent culmination of separate 

 lobes during the long period of glaciation ". 



Professor A. P. Coleman gave " An Estimate of Post-Glacial and 

 Interglacial Time in jSTorth America " ; Mr. IS". 0. Hoist gave (in 

 French) " The Beginning and End of the Glacial Period " ; Dr. Warren 

 TJpham, "The Sangamon Interglacial Stage in Minnesota and West- 

 ward." Professor T. F. W. Wolfif, "On Glacial and Interglacial in 

 North Germany," stated that there were three glaciations in that 

 region, and that at Phoben near Potsdam in one and the same bore- 

 hole two stratigraphically and faunistically distinct interglacial 

 horizons occur, the lower with Paludina diluviana and the upper 

 with P. Duboisii. 



The seventh topic for discussion was "The Physical and Eaunal 

 Characteristics of the Palaeozoic Seas, with reference to the value of 

 the Recurrence of Seas in establishing Geological Systems". Professor 

 T. C. Chamberlin contributed "The Shelf Seas of the Palaeozoic and 

 their relations to Diastrophism and Geological Systems ". Professor 

 G. Steinmann followed with " The Palaeozoic Seas in South 

 America". Professor C. Schuchert read a paper on " The Delimita- 

 tion of the Geologic Periods illustrated by the Palseogeography of 

 North America". He has drawn up eighty-five maps of North 

 American geographies since the Cambric. He proposes to divide geo- 

 logic timeinto periods based on the amount of submergence as measured 

 by the area submerged as shown on these maps. Tlie Cambrian is 

 divided into Waucobic, Acadic, Ozarkic ; the Ordovician into 

 Canadic, Ordovicic, Cincinnatic ; the Mississippian into Mississippic, 

 Tenneseic; while the Pennsylvanic and Permic are united in a single 

 system. Dr. E. 0. Dlrich discussed " The Ordovician-Silurian 

 Boundary ", and incidentally rejected Schuchert's Cincinnatic System. 

 Professor F. Freeh described " The Palaeozoics of the Bagdad 

 Eailway". Dr. 0. Holtedahl in his paper "On the Old Bed 



