Geological Society, 227 



The country around Elgin is composed of sandstones, conglome- 

 rates, and concretionary limestones, belonging to the old red sand- 

 stone ; but at Linksfield, one mile south of Elgin, that formation is 

 overlaid, unconformably, by a series of beds, which Mr. Malcolmson 

 has ascertained, by their organic remains, to represent the Wealden 

 strata of England, though they have been usually considered to be 

 lias. 



The following section gives the principal beds in descending order, 

 the average thickness of the whole series being from 20 to 30 feet : 



1. Blue clay, containing thin bands of limestone, the lower being 



shelly. 



2. Thin bands of limestone and clay. 



3. Blackish shale, not bituminous, 1 to 2 feet. 



4. Compact grey limestone, without shells, in layers separated by 



clay, 4 feet. 



5. Laminated green clay, with a network of fibrous carbonate of 



lime. 



6. Red, sandy, calcareous marl, abounding with rolled pebbles of 



granite, gneiss, &c., also angular fragments of the fine- 

 grained yellow and grey sandstone forming the hills to the 

 west, but the geological position of which is not yet ascer- 

 tained. 

 Cornstone of the old red sandstone in unconformable position. 

 The fossils are principally found in the lower bands of the top bed. 

 They are rarely well preserved, and cannot be separated from the 

 rock. The species are few in number, but abundant in individuals ; 

 and one species of Cyclas is undistinguishable from the C. media of 

 Sussex, found also by Prof. Sedgwick and Mr. Murchison in the 

 Isle of Skye : there is likewise an Avicula, which agrees with one 

 found in the Purbeck strata at Swanwich. Mr. Malcolmson procured 

 also fragments of an Astarte and a Venus, and a microscopic univalve. 

 The clay below this shelly limestone is full of the valves of a new, 

 round species of Cypris. The author also obtained teeth and scales 

 of fishes ; and the Rev. G. Gordon has found a Saurian bone. 



Fossils of the same description have been recently discovered by 

 that gentleman at Lhanbryde, three miles to the east of Linksfield ; 

 and in a micaceous white sandstone, he has procured a large Pinna, 

 which Mr. James Sowerby has identified with a species found in the 

 Portland sand of England. In April, 1832, Mr. Gordon communi- 

 cated to the Society a notice of the discovery in a dark clay*, pene- 

 trated while draining the Lake of Spynie, of the Turritella muricata of 

 the Coral Rag. Mr. Malcolmson, therefore, hopes that many members 

 of the series above the old red sandstone, not yet known to exist south 

 of the Murray Frith, will be discovered by the practical geologists 

 resident in that district. 



Mr. Martin, of the Anderson Institution, has recently discovered 

 in a bed of calciferous conglomerate, near Elgin, and supposed by 

 Mr. Gordon to represent the old red sandstone of Clasbennie in 



• Proceedings, vol. i. p. 394 j or Lend, and Edinb. Phil. Mag. vol. i, 



p. 227. 



Q2 



