Prof. Harkness on the Skiddaw Slate Series. 235 



December 17, 1862. — Prof. A. C. Ramsay, President, in the Chair. 



The following communications were read : — 



1. "On the Skiddaw Slate Series." By Professor R. Harkness, 

 F.R.S., F.G.S.; with a Note on the Graptolites, by J. W. Salter, 

 Esq., F.G.S. 



In this paper some general sections through the Skiddaw Slates 

 were described in detail, and the localities in which fossils had been 

 previously found by Professor Sedgwick were especially noticed. 

 The author then stated that he had discovered several species of 

 Graptolites new to the Skiddaw Slates in certain flaggy beds almost 

 devoid of cleavage, which occur at intervals in the lower portion of 

 the series, in several localities. Professor Harkness showed that 

 these rocks were much more fossiliferous than had hitherto been 

 supposed, and that the evidence of the fossils, as interpreted by 

 Mr. Salter, clearly proved them to be of the same age as the Lower 

 Llandeilo rocks of Wales and the Quebec Group of Canada. The 

 thickness of the Skiddaw Slates was estimated at 7000 feet, and the 

 total thickness from the base of the Skiddaw Slates to the Coniston 

 limestone at 14,000 feet. 



Besides several species of well-known Graptolites that are also 

 found in the Lower Llandeilo rocks and in the Quebec Group 

 (Taconic System), Mr. Salter has been enabled to identify Phyllo- 

 grapsus angustifolium, Hall, Tetragrapsus bryonoides, Hall, and an- 

 other species of that genus, Dichograpsus Sedgwicki, n. sp., Didymo- 

 grapsus caduceus, and some others. He has given the name of Caryo- 

 caris Wrightii to a Crustacean discovered in these rocks by Mr. 

 Wright. Mr. Salter considers the Skiddaw Slates to be of the same 

 age as the Quebec Group, the graptolitiferous rocks of Melbourne, 

 and the Tremadoc Slates of Wales. 



2. " On Fossil Estherice, and their Distribution." By Professor 

 T. Rupert Jones, F.G.S. 



Referring to the Monograph of Fossil Estherice, now in course of 

 publication by the Palaeontographical Society, for descriptions of the 

 species and for general remarks on the genus, the author in this 

 paper pointed out the chief characters of the fourteen species of 

 Estherice that he had obtained, by the help of friends at home and 

 abroad, from several of the geological formations ; and pointed out 

 that they belong mainly to the passage-groups, and, he believed, 

 chiefly to fresh and brackish waters. He also compared the distri- 

 bution of the twenty-two recent species with that of the fossil 

 Estherice. 



3. " On the Flora of the Devonian Period in North-Eastern 

 America. Appendix." By Dr. J. W. Dawson, LL.D., F.R.S., F.G.S. 



Dr. Dawson enumerated in this Appendix some additional species 

 of plants lately obtained from Perry, by Mr. Brown of that place. 

 He also stated that recent observations have shown that the beds 

 spoken of in his paper as belonging to the Catskill Group of New 

 York, really represent the Chemung Group of that State, according 

 to Professor J. Hall. 



