415 



jy the dykes in the new red sandstone; and that Dartmoor was ele- 

 vated after the deposition of the greensand, as the first traces of gra- 

 nitic debris are found in the Bovey deposit. 



A notice was next read on the supposed existence of the Lias forma- 

 tion in Africa, by Roderick Impey Murchison, Esq., F.G.S. 



Mr. Leach, of Milford Haven, a short time since presented to the 

 Society some organic remains, stated to have been obtained by Com- 

 modore Sir Charles Bullen on the west coast of Africa. As these or- 

 ganic remains agree exactly with fossils of common occurrence at Lyme 

 Regis, it was conjectured that some mistake might have occurred re- 

 specting them ; but Mr. Leach has been subsequently informed by 

 Sir Charles Bullen that they were collected by himself and officers at 

 West Bay, Fernando Po, Accra, andSierra Leone, and that they occur 

 in abundance. 



Mr. Murchison also announced in this notice, that Sir John Herschel 

 has discovered Trilobites in a rock which occurs to the north of the 

 Cape of Good Hope. 



A paper was then read, entitled " A Notice on Maria Island, on the 

 east coast of Van Diemen's Land, (S. lat. 42° 44' E., long. 148° 8',) 

 by George Frankland, Esq., Surveyor-General of the Colony; and 

 communicated to the Society by Robert W. Hay Esq., Under Secre- 

 tary of State for the Colonies. 



Maria Island is composed, for the greater part, of trap; but 

 strata of free.stone well calculated for building purposes frequently 

 occur, and at the northern point of the island is a perpendicular cliff", 

 from 200 to 500 feet high, composed of dark grey limestone, formed 

 of oysters, muscles, and other shells, in a state of great preservation. 

 On the eastern coast, near Cape Mistaken, are numerous caverns, 

 some at the height of (iOO feet above the level of the sea, the roofs 

 of which are studded with stalactites. Mr. Frankland states that Van 

 Diemen's Land in every part furnishes strong evidence of the ocean 

 having once occupied a much higher level than at present. The paper 

 also contains' much valuable information respecting the natural pro- 

 ductions of the island. 



A letter was next read on the geology of the country included in the 

 S.VT. quarter of the Daventry, or 55th sheet of the Ordnance Survey, 

 by J. Robison Wright, Esq., F.G.S. , and addressed to Capt. Mudge, 

 R.E., F.GS. 



The surface contained in this quarter sheet is about 168 square 

 miles, including the towns of Southam and Kineton, and the field of 

 the battle of Edge Hill. The formations of which the district consists 

 are the new red sandstone, the lias, and the inferior oolite. 



A notice on the occurrence of marine shells in a bed of gravel at 

 Narley Bank, Cheshire, by Sir Philip Grey Egerton, Bart., M.P., 

 F.G.S., was then read. 



In proceeding from the valley of the Weaver, at the point where it 

 is crossed by the Liverpool and Birmingham Railway, towards Dela- 



