429 



corded, that researches into the more ancient formations maybe con- 

 ducted with greater success. 



A paper was afterwards read " On the distribution of Organic 

 Remains in the Oolitic formations on the coast of Yorkshire," by 

 W. C. Williamson, Esq., Curator of the Natural History Society of 

 Manchester, and communicated by the President. 



In a former paper* Mr. Williamson gave detailed sections of the 

 lias of the Yorkshire coast, with a view to determine how far its fossils 

 might be useful in recognising the different beds of the formation at 

 other localities. The paper read at this meeting was prepared with 

 the same intent, and gave detailed accounts of the fossils of the (1) 

 inferior oolite, (2) the lower shale and sandstone, and the (3) Great 

 or Bath oolite. 



1 . The point selected by Mr. Williamson as affording the best section 

 of the inferior oolite on the Yorkshire coast is Blue Wick ; and the 

 following is the succession of the strata which it presents in ascend- 

 ing order : 



Feet. 



1. Thick beds of dark grey finely grained sandstone. . 20 



2 Irregular beds of yellow sandstone 20 



/. Hard ironshot sandstone containing small pebbles. , 1| 

 '4. Irregular beds of yellow sandstone, in some parts 



ironshot, and inclosing layers of pebbles 30 



5. Hard ironstone, many fossils 4 



(). Hard ironstone, no fossils 8 



The beds No. 1 . contain, in their lower part, argillaceous nodules 

 resembling those of the Alum shale, and inclose great numbers of 

 Ammonites striatubis, Lingula Beanii, Orbicula reflexa, and, in less 

 abundance, an Avicula resembling A. echinaia and Terebratula bidens. 

 Above this nodular bed no fossils have been noticed till within 10 feet 

 of the top of No. 1, where another layer of similar concretions occurs, 

 inclosing portions of an Astacus, resembling in some respects ^^s^a cms 

 rostratus, and a species agreeing with one found in the Cornbrash. 

 A little nearer the top of No. 1, is a thin seam containing great 

 numbers of Vermetus compressus, which is found also in the coralline 

 oolite of Yorkshire. 



The division No. 2. presents throughout its whole thickness small 

 fragments of dicotyledonous wood with an undescribed Belemnites ; 

 and towards the top are found, though rarely, Mya litterata, and still 

 higher two species of Ammonites, apparently new. 



The bed No. 3. contains the same Belemnites as No. 2, but is 

 characterized by great abundance of Terebratula trilineata. 



No. 4. is destitute of fossils, except near its junction with the over- 

 lying bed, where it contains the Belemnites and Avicula of Nos. 1. 

 and 2. 



The bed No. 5, though not more than 2 feet thick, incloses the 

 greater part of the fossils of the inferior oolite of the Yorkshire coast, 



* Gaol. Proceedings, vol. ii. p. 82. 



