422 



THE GEOLOGIST. 



as he had found similar reptilian remains in fissures at Holwell, the depo- 

 sits had been formed under corresponding circumstances. At Weston- 

 super-Mare, also, numerous remains had been found in a fissure which was 

 being worked for lead ore. 



Perceiving that a general law prevailed in all the mineral deposits of the 

 Carboniferous Limestone, the author next obtained samples from six mines 

 in the same formation, from Shropshire, Yorkshire, and Cumberland ; and 

 in four of them found organic remains more or less abundant. 



From Weardale, out of twenty-seven small samples they were obtained 

 in fourteen — the lowest being 678 feet from the surface ; they consisted 

 of Cephalopoda, Brachiopoda, univalves, Foraminifera, Echini, Encrinites, 

 Entomostraca, etc. From Alston Moor similar remains were obtained 

 from five out of eleven samples ; and from the White Mines, Cumberland, 

 in two out of seven. The most interesting results obtained from vein stuft 

 from the north of England, were from samples for which the author was 

 indebted to Mr. Eddey, of the Grassington Mines, Shipton. In one small 

 sample, which, vrhen washed, was reduced to half an ounce in weight, not 

 less than 156 specimens were found, including the little brachiopod Zellania, 

 before mentioned as occurring in the Mendip vein, though never found in 

 any stratified bed lower than the Upper Lias. Also, numerous univalves 

 and Entomostraca, and a few minute claw-like bones or spines, similar to 

 some he had found in one of the veins at Clifton. From this sample many 

 Conodonts were obtained. These were supposed to be portions of Crus- 

 tacea, but they had hitherto never been found in strata higher than the 

 Ludlow bone-bed of Silurian age. 



Owing to the highly mineralized character of the vein stuff from the 

 Conolly Mines, no organisms were observed, nor were any found in that 

 from Twaledale. From the carbonaceous-looking character of the mate- 

 rial in the latter case, the author suspected it to have been chiefly derived 

 from the coal-measures. 



Samples from a mine in Devonian, and also in Silurian strata, had been 

 examined; but, owing to their mineralized condition, they yielded no 

 organisms. 



Mr. Moore argued that all our mineral veins, from the oldest to the 

 more recent, were due to the same general laws ; that there was no evi- 

 dence of their contents having been derived from volcanic agency, nor, as 

 has also been supposed, by any electrical action removing them from the 

 adjoining rocks, and redepositing them in the veins. His view was, that 

 the fissures now containing mineral veins, when open, had, during different 

 geological periods, been traversed by the ancient seas of that time, and 

 their derived contents deposited ; and that whilst these infillings were pro- 

 ceeding, the minerals, which might previously have been held in solution in 

 the water, were, by the operation of electrical or other causes, precipitated ; 

 and_ that thus, instead of being due to volcanic action, they were to be 

 attributed to aqueous and sedimentary deposition. 



ON THE GEOLOGY OF PART OF THE COUNTY SLIGO. 



By Me. A. B. AA^tnxe. 



In this paper the author stated that he had put together a few notes upon 

 a very extensive district, which were made during a short trip in the sum- 

 mer of 1862. He alluded to the papers by Sir E. GriJEth, Bart., Arch- 



