24 DESCRIPTION OF FOSSIL TREES DISCOVERED 



This sandstone has many characteristic marks of the new red sandstone 

 formation ; but there is reason to believe that it belongs to the mountain 

 limestone series. It is about forty-five feet in height, and nearly 120 

 yards in length. It dips at an angle of 9°, in the direction of north 35' 

 east, and is underlaid at its western point by a bed of shale, containing re- 

 mains of vegetables, and dipping north 37° east, at an angle of 16°. 



At Tweed Mill, lower down the river, we find an abundant supply of 

 these singular plants. 



On the north side of the river, at Twizell grounds, a similar sandstone 

 is quarried. The position of this sandstone is altered near the bank, being 

 bent down towards the river. It dips here 8° to the north-east, but in the 

 western part of the quarry it appears to take a more regular course, and 

 dips to the south at the rate of 8°. Farther down the river, a bed of shale 

 is seen abutting against this sandstone, evidently thrown up by a fault. 

 This quarry possesses all the characters of the new red sandstone. There 

 is also a bed of sandstone quarried in the burn side close to Milnegraden. 

 It is of a grey colour, and close-grained, affording a very fine building- 

 stone. It dips at an angle of 5 to the south-south-east. 



Again, a few hundred yards to the north of Coldstream, is a thick bed 

 of very fine sandstone, belonging to the mountain limestone group, dipping 

 to the south-east. It rests upon a bed of soft bituminous shale, of un- 

 known thickness, and the beds of sandstone are streaked and irregularly 

 marked with the same substance. 



It is unnecessary here to describe the various appearances presented in 

 the neighbouring districts, in which shales and sandstones of similar charac- 

 ter prevail, all of which lie below the great mountain limestone, as de- 

 scribed by me in the Transactions of the Natural History Society of New- 

 castle-upon-Tyne. I shall therefore proceed to display the internal struc- 

 ture of the fossil stems, which occur so abundantly in these deposits. 



Their contorted and flattened shape is worthy of remark. Probably 

 their present forms may have been caused by extreme pressure, when these 

 vegetables were in a state of decomposition. It is impossible to ascertain 

 their height, as they have been fractured and dislocated. The longest stem 



