Geological Society. 369 



of Chatham and Rochester, and is characterized hy the passage of 

 the river Medway through a narrow, winding gorge bounded by 

 chalk hills. It exhibits six different deposits, viz. — Lower chalk, 

 Upper chalk, Plastic clay, London clay, Diluvium, and Alluvium. 

 An abstract of the paper is given in the "Proceedings"of the Society. 



A memoir was afterwards read " On a Fossil in the Bristol Mu- 

 seum, and discovered in the Lias at Lyme ltegis," by Dr. Riley, 

 and communicated by Charles Stokes, Esq., F.G.S., &c. 



After stating the different opinions which had been given by those 

 naturalists who had seen the specimen, and alluding to their apparent 

 incorrectness, the author states that he is induced to consider the 

 fossil as the remains of a cartilaginous fish, having many points of 

 resemblance to the Rays, but differing from them in several im- 

 portant characters. He then proceeds to give a minute description 

 of the anatomical structure of the fossil, commencing with the head. 

 He states that the jaws are very much elongated ; that he could dis- 

 cover in the upper no traces of respiratory canals or openings ; that 

 it appears to have fitted into a central groove in the lower jaw; that 

 there are no signs of any cavities for the reception of teeth; but that 

 there are lying near the jaws many spines with radiate bases similar to 

 the spines of rays and other cartilaginous fishes. The orbits are stated 

 to be of immense size, surrounded by an elevated edge or ridge, 

 and the space on each side of the median line and within these ridges 

 and corresponding to the parietal and frontal bones, to be flat and 

 depressed not unlike that of a Saurian; but the author considers 

 that this depression between the orbits may be better accounted for 

 by the fact of this part of the cranium being nothing more than a 

 thin membrane, as in some of the Chondropterygii. 



The vertebral column is said to be less injured than the other 

 parts of the animal. The processes have disappeared, but the bodies 

 of the vertebrae are perfect; they are circular and very numerous, 

 amounting to about 260, 28 of which are cervical, 143 dorsal, and 

 90 caudal. From the slight groove for the reception of the spinal 

 marrow, and the separated condition of the cervical vertebrae, the 

 author is inclined to consider the spine as having a nearer resem- 

 blance to that of a Squalus than of any other of the cartilaginous 

 fishes. 



The thoracic and pelvic members are stated to be greatly injured; 

 but from the characters which they present, it is inferred, that 

 they afford additional proofs that the fossil belonged to a cartila- 

 ginous fish. 



In conclusion, the author conceives himself justified in considering 

 the specimen as the type of a new genus, and therefore assigns to 

 it the appellation of Squalo-raia Dolichognathos. 



May 29th. — A paper " On the Oolitic Formation and its Contents, 

 as occurring in a Quarry at Bearfield, near Bradford, Wilts," by J. 

 Cbaning Pearce, Esq., F.G.S., was first read. 



The principal object of the author is to describe the organic re- 

 mains which he found in a quarry situated at the summit of the hill 

 to the north-west of the town of Bradford in Wilts, and in the same 



Third Series. Vol. 3. No. 17. Nov. 1833. 3 B 



