370 



TIIE GEOLOGIST. 



is further increased by the numerous before-mentioned bays jutting into 

 the limestone. In addition to this, over the country extending from the 

 outburst of the limestone to the sea, the large fissures already spoken of 

 as intersecting in all directions the limestone form so many channels of 

 communication between the surface and the bed of " yellow sand " down 

 which the surface drainage, and even in some instances small streams, pass 

 freely. It cannot therefore be wondered at that, when this formation is 

 pierced by any shaft below the level of saturation, large volumes of water 

 should be encountered ; and, although this may for the time increase the 

 engineering difficulties, and frequently add much to the cost of winning 

 coal through the limestone, it has at the same time its brighter points of 

 view, affording, as it does, an inexhaustible supply of pure and agreeable 

 water to the inhabitants residing on its surface. The large towns of South 

 Shields and Sunderland are entirely supplied by water pumped at exten- 

 sive works at Cleadon, "Fulwell, and Humbledon Hill. The town of Sea- 

 ham Harbour is also similarly supplied. The water is hard for domestic 

 purposes, but delightfully clear and refreshing to the taste." The general 

 strati graphical character of the magnesian limestone of the district was 

 then entered upon. The next subject was the connection between the dis- 

 location affecting the coal-measures and the magnesian limestone, this 

 portion of the paper being illustrated by reference to a forty-feet upthrow 

 fault, which passes through both the "Jane" and " Caroline" shafts of the 

 Eppleton Hetton Colliery. 



Skiddaw-Slate Fossils, and Hoenblendic G-eeenstones and theik 

 Relations to the Metamoephic and Silueian Rocks of the^ County 

 of Tteone. By Professor Harkness. 



New Coal-Plants feom Nova Scotia. By Dr. Dawson. — One of the 

 plants, L. Acadianus, belonged to the genus Lepidophloios of Sternberg ; 

 the other was an example of a type of L&pidodendron, very characteristic, 

 in Nova Scotia, of the lower coal-measures associated with the lower car- 

 boniferous limestone. The author concluded that the original species of 

 Sternberg, L. laricinum, was founded on the fragment of the bark of an 

 old trunk, having the leaf-bases flattened, and hence described as scales. 

 It was evidently, in short, closely allied to the specimen described. The 

 genus Ulodendron was, he thought, identical with Lepidophloios, but ap- 

 parently founded on specimens having the leaf-bases preserved, with the 

 cone scars, but wanting vascular scars. It appeared to him that the ge- 

 neric names Ulodendron, Lomatophloios, Leptoxylum, Pachyphlceus, and 

 Bothrodendron should be abolished in favour of Lepidophloios, unless in- 

 deed it should appear that any of these names had priority in date. The 

 second plant described was the Lepidodendron corrugation, which was 

 one of the most abundant in the lower coal-measures of Nova Scotia and 

 New Brunswick. The species was remarkable for its variability, and also 

 for the dissimilar appearances of old stems and branches occasioned by the 

 separation of the areoles in the growth of the bark, instead of the areoles 

 themselves increasing in size, as in some other Lepidodendra. 



Models illustbating the Contoetions in Mica-Schist and Slate. 

 By Mr. H. C. Sorby. — The models consisted simply of bands of india-rub- 

 ber laid upon each other. In one, the alternate bands were covered with 

 cloth, so as to deprive them of the elasticity possessed by pure india-rub- 

 ber. The object of the models was to show how various phenomena in 

 nature have probably been caused by lateral or superincumbent pressure. 

 Pressing each end of a model with a little force, Mr. Sorby easily produced 

 a series of curves and undulations, the suggestions of which were at once 

 appreciated by the Section. In the case of the model with the alternate 



