On the Estuary Beds and the Oxford Clay at Loch Staffin, in Skye

Abstract

The purpose of the following brief notice is to put on record some observations made in the island of Skye in August 1850, by which the true geological horizon of the so-called “Wealden” of Loch Staffin was determined, and the Oxford Clay added to the series of oolitic strata in the Hebrides. Sir Roderick Murchison, in his “Supplementary Remarks on the Strata of the Oolitic Series and the Rocks associated with them in the Counties of Sutherland and Ross, and in the Hebrides,” read before the Geological Society in November 1827, states that “in the low and ruinous cliff of blue shale, associated with zeolitic and amygdaloidal trap on the north-eastern shores of Loch Staffin, were found, during my late excursion with Professor Sedgwick, flattened masses of shelly limestone containing five species of Cyclas ) one Paludina , one Neritina , one Ostrea , one Mytilus , and some undescribed bivalves,” and remarks that “it adds materially to the interest of these remains, that two species of the Cyclas , the Paludina , and the Ostrea prove to be identical with the fossils of one of the upper beds of the Weald clay described by Dr. Fitton as occurring in Swanage Bay, Dorsetshire, and in the Isle of Wight.” Of these fossils a list is appended to the paper, drawn up by Mr. Sowerby; and besides the references to Weald Clay species, one Cyclas is considered identical with a Barton Cliff shell, and the Nerita is compared with a Woolwich species. When the Duke of Argyll announced