54 KEPORT — 1853. 



On the most Remarkable Cases of Unconformity among the Strata of York- 

 shire. By Professor Phillips, F.R.S. 



On the Dispersion of Erratic Rocks at higfter Levels than their Parent Rock 

 in Yorkshire. By Professor Phillips, F.R.S. 



The Professor stated that in a comparatively uiodern geological period, every part 

 of Yorkshire, below the level of 1500 feet, was covered by the waters of a glacial 

 sea. icebergs appear to have floated over the whole of this district, depositing 

 where thev melted, or were overturned, the materials brought from the higher hills, 

 which at that time were partly covered by glaciers. Amongst these were blocks of 

 stone from Cumberland and the North Riding, now found perched on the limestone 

 hills. Some of them must have come over the Pass of Stainmoor, a height of 1440 

 feet, and been thence radiated over all the eastern parts of Yorkshire. A remarkable 

 case of local distribution occurred in the country of Ribblesdale, where in several 

 places, as on Feizer and Giggleswick Scar, the blocks of ' Horton Flag ' (Carabro- 

 Silurian) were found perched on broad surfaces of limestone resting on these flags. 

 On the east side of Ribble, above Langcliffe and Settle, there were large blocks near 

 the summit, 150 or 200 feet above the level of the rock from which they were 

 derived. At Long Scar, blocks of limestone lay on the hills immediately over their 

 source. These erratic blocks were not much water-worn, and must have been trans- 

 ported by ice ; no violent rush of water would have accomplished it. He believed 

 the glacial movement to have been one of Continental elevation and depression, occu- 

 toying a long period of time, and that the assigned depression of 1500 feet affected 

 the land far up towards the north, and to the east and west, but ceased, or grew 

 knuch less, towards the south. 



On a new Plesiosaurus in the York Museum. By Professor Phillips, F.R.S. 



It was a curious circumstance, that each of the three great Plesiosauri lately dis- 

 covered in Yorkshire belonged to distinct and undescribed species. One of these, 

 described by Mr. Charlesworth at a former meeting, was now in the possession of 

 Sir P. Crampton, in Ireland ; the other two were in the York Museum. One of 

 them was 18 feet long, and had a very small head ; the other was nearly equal in size 

 to the large Plesiosaurus of the Kimmeridge clay. Its head is 42 inches long, and 

 tnuch narrower in proportion than in the other species ; the neck is much shorter, 

 being only half as long in proportion as in the P. dolichodeirus. The paddles are 

 6 feet in length, and offer analogies to Pliosaurus. The vertebrae are like those of the 

 other species ; the teeth slightly different. It was found in Lord Zetland's works, 

 at Lofthouse, on the Yorkshirs coast. 



On the Formation of Boulders. By the Rev. T. Rankin. 



The writer's observations were made in some of the valleys on the Scotch borders, 

 with the view of exciting Mr. Hopkins to re-examine the theory which he had em- 

 braced with some hesitation, and whether it be tenable. Mr. Rankin endeavoured 

 to explain the phsenomena of the boulder formation by a general deluge, and subse- 

 quent river-action. 



On the Classification and Nomenclature of the older Pala:ozoic Rocks of Britain. 

 By the Rev. Professor Sedgwick, M.A., F.R.S., &c. 

 The term Palaeozoic includes all the known fossiliferous rocks from the Permian 

 to the lowest Cambrian. It is separated into three natural divisions : — 1st. Lower 

 division, including all deposits which have been called Cambrian and Silurian. 

 2nd. Middle division, including the Old Red Sandstone ; and the whole Devonian 

 series, of which the lowest group appears to be wanting in the English sections. 

 3rd. Upper division, including the Carboniferous and Permian series. If the old terms. 

 Primary, Secondary and Tertiary, be retained, the three above-named divisions make 

 up the Primary System of Britain ; and to these divisions, collectively, the author 

 applies the term Palceozoic System. They do not interchange species with the fossils 



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