BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA 



VOL. 27, PP. 555-622 NOVEMBER 29, 1916 



PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY 



COMPARISON OP AMERICAN AND EUROPEAN LOWER 

 ORDOVICIC FORMATIONS 1 



BY AMADEUS W. GRABATJ 



(Presented before the Paleontohgical Society December SO, 1915) 



CONTENTS 



Page 

 Introduction 556 



Lower Ordovicic of Europe and North America compared 557 



Lower Ordovicic of North Scotland and its relation to similar deposits 



elsewhere 560 



General petrographic and f aunal characteristics 560 



The northern sections 561 



Table of Ordovicic species from the Durness limestone 566 



Discussion 569 



Biri limestone of Norway 570 



Lower Ordovicic of the Atlantic region • 573 



Tremadoc 573 



Arenig 574 



General discussion 574 



Scotland 575 



Lake district '. 578 



Wales 578 



Normandy and Brittany 573 



Mediterranean region 581 



Iberian Peninsula 581 



Montaigne Noire, southern France 583 



Bohemia 583 



Lower Ordovicic of the Baltic region 585 



The Orthoceras limestone 585 



The Orthoceras limestone of Esthonia 590 



Correlation of the East Baltic and Scandinavian horizons 601 



Lower Ordovicic of Dalarne 604 



Ordovicic of Jamtland 60S 



Lower Ordovicic of the Christiania region 609 



Ordovicic of (Eland 610 



Ordovicic of Scania 611 



1 Manuscript received by the Secretary of the Geological Society August 25, 1916. 

 This is the first of a series of comparative studies of the European and American 

 Paleozoic, based on investigations and collections made by the writer during eight 

 months' sojourn in northern Europe in 1910. 



XLI— Boll. Geol. Soc. Aw., Vol. 27, 1915 (555) 



