260 Prof. Lajnvorth — Palceozoic Rods of Britain S^ Scandinavia. 



V. — On the Cokkelation of the Lower Paleozoic Eocks of 

 Britain and Scandinavia. 



By Charles Lapworth, F.G.S., etc., 

 Professor of Geology and Mineralogy, Mason Science College, Birmingham. 



N the pages of the Geol. Mag., about a year ago,^ I called attention 

 to the rapid growth of our knowledge of the sequence and 

 fossils of the Lower Paleeozoic Eocks of Sweden, through the brilliant 

 discoveries of the officers of the Swedish Geological Survey ; and 

 pointed out what appeared to myself to be their special bearing 

 upon certain controverted points in British Geology. During the 

 past year the additional results obtained by the same group of earnest 

 and unprejudiced observers are so important in themselves, and have 

 been worked out with such care and elaboration, that we have now 

 a tolerably complete view of the entire Lower Palaeozoic Succession 

 in the Scandinavian Peninsula, and are, for the first time, in a 

 position to attempt the detailed correlation of its recognized rock 

 groups with their representatives in Britain. 



It is now at least some thirty-six years since Murchison made his 

 first attempt to parallel the Scandinavian Succession with that 

 worked out by himself in the West of England ; ^ and more than 

 fourteen years since he put the finishing touches to this parallel in 

 the classic pages of " Siluria." ^ To those who have not attentively 

 studied the recent advances in our knowledge of the Lower Pala30zoic 

 formations of Britain, Murchison's parallel still appears sufficient 

 for all scientific purposes. But all earnest students of British 

 Paleozoic geology are well aware, that although satisfactory enough 

 in its day, it has long ceased to be of any practical value ; while, 

 at the present time, it has the jDositive disadvantage of hiding from 

 geologists in general the many striking correspondences now known 

 to exist between the Lower Palfeozoic formations in Britain and 

 Scandinavia. In the present memoir, therefore, I propose, while 

 directing attention to the valuable data recently supplied us by the 

 geologists of Sweden and Norway, to treat of these data in geological 

 sequence, to indicate as briefly as possible, a few of the chief points 

 of identity or similarity between the Lower Paleeozoic formations as 

 developed in Britain and Scandinavia, and to construct therefrom 

 a new parallel that shall summarize our present knowledge, and 

 afford the working geologist a general idea of the lines upon which 

 his future investigations may most profitably be directed. 



Section I. — Cambrian System. 



Under the name Cambrian I include, with Dr. Hicks, all the 

 fossiliferous strata lying between the basal beds of the Harlech 

 Eocks as shown at St. Davids, and the provisional line drawn at 

 present between the Lower and Upper Tremadoc Beds of Sedgwick 



* Lapworth, On Linnarsson's Recent Discoveries in Swedish Geology, — Geologi- 

 cal Magazine, 1880, pp. 29, 68, et. seqq. 



^ Murchison, Quart. Journ. Geol. Soc. vol. i. p. 467, 1845. 

 3 Siluria, fourth edition, p. 348, et seq., 1867. 



