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Accouitt of a Depo,fite of' Fossil Plants, discovered in the Coat 

 Formation of the Third Secondary Limestone, near Scar- 

 birrough. With a Plate. By Peter Murray, M. D. Com- 

 municated by the Author *. 



An interesting geological discovery has lately been made near 

 Scarborough, in Yorkshire, in Gristhorpe Bay, of a large depo- 

 site of fossil plants of the coal formation, presenting many varie- 

 ties hitherto undescribed. 



They occur in the strata called Coaly Grit by Mr William 

 Smith, a pseudo coal-field below the corn-brash, but far above 

 the coal measures of any moment, being superior even to the 

 Oxford clay, marl-stone and lias. The thin seams of coal which 

 accompany these plants are the highest in this vicinity, overtop- 

 ping the Bath or inferior oolite ; which again is above the other 

 veins of bad coal which rise over the lias beds to the north, and 

 contain similar vegetable remains, along with a singular arundi- 

 naceous stem, called by Mr Merchison Oncylogonatum carbona- 

 rium. 



The Gristhorpe petrifactions appear in a fissile indurated clay, 

 passing into a soft grit, and occasionally alternating with clay 

 iron-stone, which is replete with nodules, intersected with veins 

 of calcareous spar, and generally in the centre containing some 

 vegetable impressions, for the most part varying from those in 

 the clay ; and, on account of the hardness of the stone itself, of 

 greater sharpness and preservation. The plants lie layer above 

 layer horizontally, and those of the same species (with some ex- 

 ceptions) occurring together, as if the hxralities of each had been 

 extremely limited, and apparently as they had been swept down 

 by a great and sudden torrent of water, many being laid, the 

 one crossing the other ; or bent partly underneath one branch, 

 and then thrown over another, and some of the leaflets, as it 

 were, squeezed together : Some very small and young ; othei's 

 large ; others again even in fructification ; and several of the spe- 

 cimens of considerable magnitude and beauty, and in admirable 

 preservation. 



* The secondary limestones at present known are the following : 1. First 

 or Magnesian Limestone ; 2. Second or Shell Limestone ; 3. Third, including 

 Lias, Oolite, &c. ; 4. Fourth or Chalk — Edit; 



