PROCEEDINGS OF GEOLOGICAL SOCIETIES. 



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PROCEEDINGS OF GEOLOGICAL SOCIETIES. 



Liyeepool Geological Society. — Amongst the papers of the last ses- 

 sion are : — " On the Ancient Glaciers of Snowdon," by Mr. G. H. Morton, 

 who gives an account of the experiences of two days spent on the moun- 

 tain, and describes the group included under that name, — the highest 

 peak, Pen Wyddfa, being 3571 feet above the sea. " On the Lingula- 

 Hags and Strata beneath," by the same author, who describes at con- 

 siderable length the principal localities in Europe and North America 

 where the Lingula-flags and Lower Llandeilo strata are developed, and in 

 conclusion, states that " the fossils of the Lingula-flags embraced many 

 varieties of form, and that though there are cosmopolitan species, there are 

 others of more limited range in space. The result of geological investiga- 

 tion in the Cambrian rocks has brought to light but very scanty traces of 

 early life, it being only in the strata of that age, at Church Stretton and 

 Bray Head, that any such indications have been found. It is, however, 

 remarkable that crystalline limestone should occur in the still lower Lau- 

 rentian system, for if this rock was formed, like other limestones, of com- 

 minuted fragments of shells and corals, since altered by a high tempera- 

 ture, then the theory of such rocks being azoic is groundless, and we have 

 yet to become acquainted with the most ancient life -creation." 



Eeport of the Field Meeting at Store-ton, on Monday, the 7th of 

 July, 1862, — when Mr. Morton exhibited for the first time a section 

 drawn to scale, showing each important bed that occurs in the oldest of 

 the Storeton quarries — the south quarry. The interesting faults, and the 

 position of the Keuper Sandstone, in a fissure of the Bunter Sandstone, 

 cause this section to be very remarkable and instructive. 



A field meeting was held at Leasowe, September 20th, 1862, when the 

 members visited the interesting sections of the submarine forest beds at 

 Leasowe Lighthouse and Dove Point. 



" On the Geology of the Thames Valley." By Mr. W. S. Hoi-ton, F.G.S. 

 The physical features of the district consist of a succession of low terraces 

 overlooking the valley of the Thames, or Isis, presenting to the course of 

 that river their more abrupt flanks, and gently sloping down in the oppo- 

 site direction. This terrace-like succession is a true index to the stratigra- 

 phical structure of the district, as it will be found that each of them is com- 

 posed either of limestone or some other firm rock, resting upon a basis of 

 clay, which forms the intervening valley. The formations occupying the 

 tract of country described in this paper are in descending order ; the Post- 

 Pliocene (represented by the high-level gravel and the estuarine, or low- 

 level gravel) ; the Lower Cretaceous (the Shotover Sand and Lower Green- 

 sand) ; and the Upper and Middle Oolites, consisting of the Purbeck beds, 

 Portland Stone and Sand, Kimmeridge Clay, Upper Calcareous Grit, Coral 

 Rag, Lower Calcareous Grit, and Oxford Clay. The Oxford Clay occu- 

 pies a considerable area, extending northward from the ridge of the Coral 

 Hag, but, as for the most part it is level ground, and generally covered by 

 the Estuarine gravel, but very few sections occur. Its thickness is very 

 considerable ; at Wytharn Hill it was ascertained from a boring to be 600 

 feet ; it is, however, probable that thickness is somewhat exceptional, as at 

 St. Clement's, on the other side of Oxford, it is reduced to 265 feet. Crys- 

 tals of selenite and iron pyrites occur, but fossils are by no means plentiful, 

 and only locally preserved. The Coral Eag and its associated beds — the 

 Upper and Lower Calcareous Grits — form a low terrace, rising somewhat 



