3. On the RECENT EARTHQUAKE at ST. HELENA. [Communicated by the Colonial Secretary through Sir C. Lyell, Bart., [Abstract.] THIS earthquake, which is stated to be the fourth that has occurred during the two centuries that we have been in the occupation of the Island, occurred at about 4h. 10m. A.M. on July 15th, and in this paper Sir C. Elliot described the nature of the shock and the circumstances attending it. NOVEMBER 23. William Stephen Mitchell, Esq., of Gonville and Caius College, Cambridge, was elected a Fellow. 1. On the OCCURRENCE of ORGANIC REMAINS in the LAURENTIAN ROCKS of CANADA. By Sir W. E. LOGAN, LL.D., F.R.S., F.G.S., Director of the Geological Survey of Canada. THE oldest-known rocks of North America are those which compose the Laurentian Mountains in Canada and the Adirondacks in the State of New York. By the investigations of the Geological Survey of Canada, they have been shown to be a great series of strata, which, though profoundly altered, consist chiefly of quartzose, aluminous, and argillaceous rocks, like the sedimentary deposits of less ancient times. This great mass of crystalline rocks is divided into two groups, and it appears that the Upper rests unconformably upon the Lower Laurentian series. The united thickness of these two groups in Canada cannot be less than 30,000 feet, and probably much exceeds it. The Laurentian of the West of Scotland also, according to Sir Roderick Murchison, attains a great thickness. In that region the Upper Laurentian, or Labrador series, has not yet been separately recognized; but, from Mr. McCulloch's description, as well as from the specimens collected by him, and now in the Museum of the Geological Society of London, it can scarcely be doubted that the Labrador series occurs in Skye. The labradorite and hypersthene-rocks from that island are identical with those of the Labrador series in Canada and New York, and unlike those of any formation at any other known horizon. This resemblance did not escape the notice of Emmons, who, in his description of the Adirondack Mountains, referred these rocks to the hypersthene-rock of McCulloch, although these observers on the opposite sides of the Atlantic looked upon them as unstratified. In the Canadian Naturalist' for 1862, Mr. Thomas McFarlane, for |