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2. Notice on the Geology of Gottland, from the Observa- 

 tions of Mr Laing. By Dr Traill. 



The fine Map of Sweden by Hissenger shews that the greatest 

 part of that kingdom, to beyond the 61° N. Lat., may be charac- 

 terized as a vast gneiss formation, skirted on the SW. and NE. by 

 extensive detrital or alluvial formations. 



The g^ieiss is interspersed with considerable tracts of granite, 

 especially in the province of Ostergottland, and here and there ex- 

 hibits small portions of hornblende-rock, porphyry, quartz-rock, 

 mica-slate, and primary sandstone ; but these rocks scarcely form 

 any considerable tracts, and the scarcity of mica-slate is rather re- 

 markable in a gneiss country. 



The alluvial deposits consist of vast beds of clay, sand, and gra- 

 vel, interspersed with greywacke-slate and transition limestone, 

 with some mountain or encrinal limestone, lias beds, and oolite, and 

 sparingly dotted with trap-rocks. The only considerable assem- 

 blages of these latter rocks are in two patches between the vast 

 lakes the Wenern and the Wettern. 



The constitution of the two most considerable Swedish islands, 

 Oland and Gottland, are still more simple. They chiefly consist of 

 encrinal limestone. 



Gottland has a length of about seventy-six English miles, and its 

 greatest breadth is thirty-four miles. Its general surface is flat, and 

 in no point does it rise more than 200 feet above the sea. About 

 one-tenth of its surface exhibits an oolitic limestone, bordered by a 

 narrow stripe of sandstone on each side ; which evidently belongs to 

 the oolitic formation, from the nature of the organic remains found 

 in them. 



Petrifactions found in Gottland. 



A. In the Mountain Limestone. 



Crustacea Gasteropoda 



Calymene, 4 species. Euomphalus, 4 species. 



Asaplius caudatus. Turritella cingulata. 



Cj^herina Balthica. Acephala 



Cephalopoda Modiola Gothlandica. 



Orthoceratites, 5 species. Tellina Gothlandica. 



Ammonites Dalmanni. Bradiiopoda 



Nautilites complanatus. Septaena, 4 species. 



Gasteropoda Orthis, 5 species. 



Turbinites, 2 or 3 species. Eyrtia, 2 species. 



Delphinula, 6 species. 



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