Geological Society, 231 



dantly. Five species are stated to be common to the Kelloway rock 

 and the combrash, and ten to the Kelloway rock And the coralline 

 oolite. Remains of fishes and of Ichthyosauri and Plesiosauri also 

 occur in the deposit. 



Oxford Clay. — ^This great argillaceous formation is about 130 feet 

 thick, and consists chiefly of fissile shales, but towards the upper part 

 it becomes sandy. Fossils are comparatively rare in it, and are con- 

 fined to the lower part, the only shell discovered in the upper by Mr. 

 Williamson being Pinna lanceolata. The characteristic fossils are 

 Ammonites Vernoni, A. cristatus, A. athleta, A. occulatus, Belemnites 

 gracilis, Nucula nuda, N. elliptica, Pinna mitis, Astarte lurida,A. ca- 

 rinata, Avicula expansa. The bed resting on the Kelloway rock is 

 characterised by Belemnites abbreviatus and Gryphaa bullata. 



In future communications, the author purposes to illustrate the 

 distribution of organic remains in the higher oolitic strata of the 

 Yorkshire coast, 



A paper was afterwards read, " On the State in which Animal 

 Matter is usually found in Fossils ;" by Mr. Alfred Smee, Student 

 of King's College, London, and communicated by Prof. Royle, M.D„ 

 F.G.S. 



The author first describes briefly, the composition of those parts 

 of recent animals capable of being preserved in a fossU state ; and 

 then proceeds to detail his investigations into the composition of 

 fossil organic remains. 



For the sake of arrangement, he divides fossils into two great 

 classes, one in which animal matter is present in various states, the 

 other in which it has been removed. The first class he further sub- 

 divides into three cases : 1. comprehending those fossils in which 

 animal matter retains its original condition ; 2. those in which it 

 has been partially changed; 3. those in which only the carbon of 

 the animal matter remains. 



1 . The following examples were given of the first case. 



Small portions of the tooth of a horse, of an ox, and a stag, from 

 the chalk rubble at Brighton, were submitted to the action of diluted 

 muriatic acid ; and after the earthy portions had been removed the 

 animal matter retained the shape of the bone, was white, and of the 

 consistence of cartilage. Fragments of a tooth of a mammoth from 

 Norfolk, and of a rib of a mastodon from Big-bone-lick in Ohio, when 

 similarly treated, gave the same results. A thin slice of the rib ex- 

 hibited under the microscope the stinicture of recent bone. Frag- 

 ments of a stag's rib and horn, of an ox's head, and the tusk of a 

 boar found near the Bank of England, associated with Roman imple- 

 ments, retained their animal matter unaltered. Small portions of a 

 Terebratula and of tv/o species of Productse, from the Silurian rocks of 

 Malvern, were placed in very diluted muriatic acid, and when the 

 earthy portions had been removed, small flocculi of animal matter, re- 

 sembling the recent membrane of a shell, floated in the solution. A 

 minute fragment of Asaphus caudatus yielded little shreds of animal 

 matter. The experiments on the shells were repeated several times 

 with the same results. Under the microscope these fossils exhibited 

 also the structure of recent shells. 



