part 1] PROCEEDINGS OF THE GEOLOGICAL SOCIETY. V 



2. ' The Petrography and Correlation of the Igneous Eocks of 

 the Torquay Promontory.' By William George St. John Shannon, 

 M.Sc, F.G.S. 



Lantern-slides were exhibited in illustration of Mr. W. A. 

 Richardson's paper, and rock-specimens and lantern-slides in 

 illustration of Mr. W. G-. Shannon's paper. 



January 10th, 1923. 



Prof. E. J. Garwood, Sc.D., F.R.S., Vice-President; and after- 

 wards Prof. A. C. Seward, Sc.D., F.R.S., President, in the Chair. 



The List of Donations to the Library was read. 



The following Fellows, nominated by the Council, were elected 

 Auditors of the Society's Accounts for the preceding year : — 

 Frederick Noel Ashcropt, M.A., and Richard Mountford 

 Deeley, M.Inst.C.E. 



Prof. William Johnson Sollas, Sc.D., F.R.S., F.G.S. , then 

 proceeded to deliver a lecture on Man and the Ice-Age. 



He said that, thanks to the researches of General de Lamothe, 

 Prof. Deperet, and Dr. Gignoux, the Quaternary System now takes 

 its place as a marine formation in the stratified series. 



Four ancient coast-lines, of remarkably constant height, have 

 been traced around the Mediterranean Sea and along the western 

 shores of the North Atlantic Ocean. These, with their associated 

 sedimentary deposits, form the successive stages of the Quaternary 

 System : namely, the Sicilian (coast-line about 100 metres) ; the 

 Milazzian (coast-line about 60 m.) ; the Tyrrhenian (coast-line 

 about 30 m.) ; and the Monastirian (coast-line about 20 m.). 



The Sicilian deposits rest unconformably upon the Calabrian 

 (Upper Pliocene), and in their lower layers contain a characteristic 

 •cold fauna. The fauna of the Milazzian is warm-temperate, of the 

 Tyrrhenian and Monastirian still warmer, for they contain numerous 

 species of mollusca which now live off the coast of Senegal and 

 the Canary Islands. 



The three lower coast-lines correspond with the three lower 

 river- terraces of the Isser (Algeria), the Rhone, and the Somme. 

 Hence it may be inferred that the position of the river-terraces 

 has been determined by the height of the sea-level. 



The lower gravels of the three lower terraces of the Somme all 

 •contain a warm fauna, Elephas antiqims and Hippopotamus, and 

 thus (like the corresponding marine sediments) testify to a warm 

 climate. The climate of the Quaternary age was, on the whole 



