184 Reports and Proceedings. 



Professor John Young, M.D., F.E.S.E., F.G.S., President, in the 

 chair. 



Mr. James Thomson, F.Gr.S., exhibited several specimens of 

 chlorite schist from Port-Askaig, Islay, with imbedded angular and 

 rounded fragments of granite, varying in size from one-eighth to 

 twenty inches in diameter. Mr. Thomson was not aware that granite 

 had been found in situ in the island, consequently the pieces must 

 have been transported from a distance, probably by ice, and imbedded 

 in the chlorite schist during its deposition. The granites are of two 

 kinds, one resembling a fine-grained variety of a dull red colour 

 found in Glencoe, the other resembles the granite of the Eoss of 

 Mull. If the presence of these granites might be attributed to the 

 agency of ice, it would imply a Glacial period during the deposition 

 of the schistose rocks of the Western Highlands. 



Mr. Thomson also exhibited a large suite of fish and reptilian re- 

 mains from the blackband ironstone of Quarter, near Hamilton, which 

 the President pointed out in detail, and expressed a desire that they 

 might be figured and described in the publications of the Society. 



Mr. Hugh M'Phail, of Nitshill, read a paper on " the Carboniferous 

 Sections of the Levern Valley," illustrated by a cross section from 

 Waukmill Glen to Crookston Hill, representing the succession of the 

 beds from the Hurlet and Nitshill main coal series upwards. The 

 valley of the Levern is divided into two portions, the southern being 

 drained by the Aurs, joined by the Brock, and the northern by the 

 Levern, the natural trough of the valley being in the southern divi- 

 sion. Commencing at a brown sandstone, a few feet from the surface 

 in the centre of the trough, Mr. M'Phail described the lithological 

 character of the different strata down to the base of the section, em- 

 bracing upwards of three hundred fathoms. The strata on the 

 southern side of the valley rest upon the Trap, and on the northern 

 side at Crookston they are much altered by an igneous dyke. Four 

 great faults traverse the valley in a direction nearly east and west, 

 which are crossed by smaller faults at various angles. These have 

 produced upthrows of the strata to the westward. As the valley 

 narrows towards the west the strata attain a high angle, and are 

 gradually thrown off, and in the bed of the Levern at West Arthurlie, 

 Gateside, and near Broadley Mill, they are seen dipping at various 

 angles. The geological phenomena along the south of the valley, 

 and at the base of the Fereneze and Brownside hills, strongly in- 

 dicate that the Trap has been elevated through the Carboniferous 

 strata. It would appear from the angles at which the faults cut 

 the trough that they could not have been formed by a depression of 

 the valley ; but, viewed in connection with the smaller cross faults, 

 it seems evident that an upheaval of the igneous rocks has taken 

 place on both sides of the valley, The ranges of hills above referred 

 to appear to have had a greater elevation than they now possess, and 

 to have been again depressed, carrying down with them the strata on 

 and adjacent to their base. From the formation of the trough, Mr. 

 M'Phail was of opinion that the beds had been deposited on eleva- 

 tions on each side of the valley, and that these elevations were at a 



