Professor E. Forbes on (he Oolite in Skye. 93 



** Wealden" of Loch Stafl&n 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 Novem- 

 ber 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 Palu- 

 dinuy one Neritina, one Ostrea, one Mytilus, and some unde- 

 scribed 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 refer- 

 ences to Weald clay species, one Cyclas is considered iden- 

 tical with a Barton Cliff shell, and the Nerita is compared 

 with a Woolwich species. 



When the Duke of Argyll announced his important dis- 

 covery of tertiary strata, probably of freshwater origin, asso- 

 ciated with traps in the island of Mull, it occurred to me that 

 possibly the Loch Staffin beds might prove to be tertiaries 

 also ; the more likely since some of their fossils had been 

 referred to tertiary species. At the same time I felt very 

 anxious to ascertain whether on the other hand they might 

 really be Wealden strata, or what was more probable, as Mr 

 Robertson had suggested in his interesting paper on Brora, 

 equivalents of the estuary strata associated with the Brora 

 oolitic coal. My recent researches among the Purbecks had 

 led me to distrust all the older determinations and compari- 

 sons of freshwater fossils, and I felt that it was of great con- 

 sequence to the special work in which I was officially engaged 

 in my duties as a member of the Geological Survey, that 

 before publishing the full account of the palaeontology of the 



