671 



opinion that the Sternbergia was not accidentally allocated with the 

 larger stem, but that it was, while living, a parasite, and in this 

 respect resembled the mighty creepers of the existing tropical 

 regions. 



A paper was next read, " On the Distribution of Organic Remains 

 in part of the Oolitic Series on the coast of Yorkshire;" by Mr. 

 Williamson, Curator of the Natural History Society of Manchester. 



In former communications* Mr.Williamson explained the vertical 

 range of organic remains in the Lias of inferior and great oolites, and 

 in this he showed their distribution in the upper sandstone and shale, 

 the combrash, the Kelloway Rock, and the Oxford Clay. 



The upper sandstones and shales vary considerably in their characters, 

 but they consist of three principal divisions, the highest and lowest 

 being composed of sandstones sometimes ferruginous, and the middle 

 one of clays and shales. The principal localities for the fossils are on 

 the north side of Scalby Beck, near Scarborough, and Burniston Bay. 

 The most characteristic plants are Pecopteris Murrayana, Cyclopteris 

 digitata, and Otopteris ohtusa ; but remains of Cycadese and Equiseta 

 also occur. The list of plants is much smaller than that generally 

 given, in consequence of Mr, WUliamson having removed to the great 

 oolite, a bed generally considered as belonging to the upper sand- 

 stones. 



Cornbrash. — This formation seldom exceeds five feet in thickness, 

 and in Cayton Bay consists of the following strata in descending 

 order : 



FissUe oolite 6 inches. 



Softer rock, sometimes ironshot . . 2 feet. 



Hard ironshot rock 2 feet. 



Blue clay, from 3 inches to 4 feet. 



The fossils contained in the fissile upper bed, are chiefly Terebra- 

 tula ovoides, T. ohsoleta, Ostrea edulina, and 0. Marshii. The greater 

 portion of the organic remains are found towards the middle of the de- 

 posit, the following being the most abundant : Ammonites Herveyi, 

 Ostrea Marshii, Plagiostoma rigidulum, P. interstinctum, Trigonia 

 clavata, T. costata, Cardium citrinoideum, Unio peregrinus, Amphidesma 

 decurtatum, A. securiforme, My a literata, and Clypeus orbicularis. 

 Twenty other species also occur, but less numerously. In the bed of 

 clay, remains of a ^Toei}! Astacus (?) are obtained, also a shell resem- 

 bling an Unio, and an undescribed Belemnite. Thirteen of the species 

 found in the combrash are stated to exist also in the great oolite of 

 Yorkshire, and nine in the coralline or Oxford oolite. 



Kelloway Rock. — ^This deposit consists of soft sandstones, some- 

 times calcareous, but towards the top it is occasionally very ferrugi- 

 nous ; and it varies in thickness from 35 to 70 feet. The fossils are 

 numerous and highly characteristic, particularly the Ammonites. 

 The ferruginous bed is full of organic remains, consisting chiefly of 



* Proceedings, vol. ii., pp. 82, 429. Geol. Trans., vol. v. Part I., p. 223, 

 €t seq. 



3 K 



