146 Geological Society : — 



GEOLOGICAL SOCIETY. 

 [Continued from vol. xliii. p. 544.] 



February 7, 1872. — Joseph Prestwich, Esq., F.ll.S., President, 



in the Chair. 

 The following communications were read : — 



1. ''Further ITotes on the Geology of the neighbourhood of 

 Malaga." By ]M. D. M. d'Oruela. Communicated by the President. 



In this paper, which is a continuation of a former note laid 

 before the Society (see Q. J. G. S. xxvii. p. 109), the author com- 

 menced by stating that his former opinion as to the Jurassic age of 

 the rocks of Antequera is fully borne out by later researches upon 

 their fossils. They apparently belong to the Portlandian series. 

 The author made considerable additions to his description of the 

 Torcal, near the foot of which he has found a sandstone containing 

 abundance of Gryplicm virgida and Ostrea deltoidea. This he re- 

 gards as equivalent to the Kimmeridge Clay. In the Torcal he has 

 also found a soft, white, calcareous deposit, oyerlying the limestones of 

 supposed Portlandian age, and containing a fossil which he identifies 

 with the Tithonian Terebratida dipJiya. The author discussed the 

 peculiar forms assumed by the rocks of the Torcal under denuda- 

 tion, which he supposed to be dae originally to the upheaval caused 

 by the rising of a great mass of greenstone, portions of which are 

 visible at the surface on both sides of the range. 



2. " On the Eiver-courses of England and Y/ales." By Prof. A. 

 C. Eamsay, LL.D., F.P.S., F.G.S. 



The author commenced by describing the changes in the physical 

 conformation of Britain during the Jurassic and Cretaceous periods, 

 and the relations which the deposits found during those periods bore 

 to the Pala3ozoic rocks of Wales and the north-west of England. 

 He stated that the Miocene period of Europe was essentially a con- 

 tinental one, and that it Vv^as closed by important disturbances of 

 strata in Central Europe, one effect of which would be to give the 

 Secondary formations of France and Britain a slight tilt towards 

 the north-west. To this he ascribed the north-westerly direction 

 of many of the rivers of France ; and he surmised that at this 

 period the rivers of the middle and south of England also took a 

 westerly course. The westerl^^ slope of the Cretaceous strata of 

 England was also, he considered, the cause of the southern flow 

 of the Severn, between the hilly land of Wales and the long slope 

 of chalk rising towards the east. The Severn would thus establish 

 the commencement of the escarpment of the Chalk, which has since 

 receded far eastward. 



The author believed that after the Severn had cut out its valley 

 the Cretaceous and other strata were gradually tilted eastwards, 

 causing the easterly course of the Thames and other rivers of 

 southern and eastern England. In these and other cases adduced 

 by the author, the sources of these rivers were originally upon the 

 Chalk near its escarpment ; and it is by the recession of the latter 



