412 Geological Society: — 



January 13, 1875. — John Evans, Esq., F.B.S., President, 

 in the Chair. 

 The following communications were read : — 



1. "On the Kimmeridge Clay of England." By the Eev. J. F. 

 Blake, M.A., F.G.S. 



The author described in considerable detail the development of the 

 Kimmeridge Clay in various parts of England, dwelling especially 

 upon the palseontological phenomena presented by it in the different 

 localities. He arrived at the conclusion that the Kimmeridge Clay 

 in England is divisible only into two sections, Upper and Lower ; 

 but when it is preceded by the Coral Rag, it possesses a basal series 

 of no great thickness, which may be designated the Kimmeridge 

 Passage-beds. He compared his Upper Kimmeridge with the lower 

 part of the " Yirgulien" of foreign authors. It consists of paper 

 shales, paper slabs, bituminous shales, and cement stones, with 

 inters tratined clays, and may attain a thickness of at least 650 feet. 

 Its fauna is characterized by paucity of species and great abundance 

 of individuals. It is thickest in Dorsetshire and Lincolnshire, but 

 thin or absent in the inland counties. The author stated that no Eauna 

 comparable with that of the Middle Kimmeridge or " Pterocerien " 

 has been discovered in England, though some of its less-charac- 

 teristic fossils occur associated with Lower-Kimmeridge forms. The 

 Lower Kimmeridge is a mass of blue or sandy clay, with numerous 

 calcareous " doggers," largely developed in Lincolnshire, the whole 

 representing the " Astartien" of foreign geologists. Its thickness is 

 estimated at from 300 to 500 feet in Eingstead Pay, and about 400 

 feet in Lincolnshire. The fossils of the Coral Eag extend up into 

 the Kimmeridge passage-beds, which are typically developed at "Wey- 

 mouth, where they are about 20 feet thick. 



2. " Note on Pelohatochelys Blcdci and other Vertebrate Fossils 

 obtained bv the Eev. J. F. Blake from the Kimmeridge Clay." By 

 Harry Govier Seeley, Esq., F.L.S., F.G.S., Professor of Physical 

 Geography in the Bedford College, London. 



The author stated the fossils referred to in his paper gave evidence 

 of three species of Ichthyosaurus (one larger than any previously 

 known to occur in the formation), a PHosaurus, a Stereosaurus, a 

 small Ornithosaurianj and a species of Chelonian, which he described 

 under the name of Pdobatocliclys Blalcei. The remains of this 

 animal indicated a carapace 16 inches long by 14 inches broad, aud 

 angularly arched posteriorly. The pygal scute was divided as in 

 Emys ; and the hinder margins of the vertebral scutes were elevated 

 as in some species of Baiarjur. The vertical scutes were nearly 

 twice as broad as long, and interlaced with each other by sawliko 

 margins. The costal plates were imperfectly ossified. 



3. " On the Cambridge Gault and Grccnsand." By A. J. Jukes- 

 Browne, Esq., F.G.S. 



This paper has for its object to determine the true position of the 

 Cambrige nodule-bed in the Cretaceous series, and to investigate the 

 nature and origin of its peculiar fauna. 



