XC PROCEEDINGS OE THE GEOLOGICAL SOCIETY. [vol. LXXIV, 



June 5th, 1918. 



Mr. G. W. Lamplugh, F.R.S., President, 

 in the Chair. 



The List of Donations to the Library was read. 



The following communications were read : — 



1. ' The Kelestominse, a Sub-Family of Cretaceous Cribrimorph 

 Polyzoa.' By William Dickson Lang^ M.A., F.G.S. 



2. ' The Geology and Genesis of the Trefriw Pvrites Deposit.' 

 By Robert Lionef Sherlock, D.Sc, A.R.C.Sc, F.G.S. 



Lantern-slides of Cretaceous polyzoa were exhibited by Mr. W. D. 

 Lang, in illustration of his paper. 



Rocks, minerals, and fossils were exhibited by Dr. R. L. Sherloc c, 

 in illustration of his paper. 



June 19th, 1918. 



Mr. G. W: Lamplugh, F.R.S., President, 

 in the Chair. 



Alfred Joseph Bull, B.Sc, 16 Vincent Road, Croydon ; Capt. 

 Edward Lionel Johnson, R.E., 91 Bruce Street, Swindon (Wilt- 

 shire) ; and William McPherson, Masons Arms Hotel. Muirkirk 

 (Ayrshire), were elected Fellows of the Society. 



The List of Donations to the Libraiy was read. 



A Lecture on Some Features of the Antarctic Ice-Cap 

 was delivered by Major Sir Douglas Mawhon, D.Sc, F.G.S. In 

 the course of his lecture, which was illustrated by a large series of 

 lantern-slides, Sir Douglas Mawson said that the ice-mantle of the 

 south formerly involved the sub- Antarctic Islands, Patagonia, 

 Southern New Zealand, and the higher mountains of Tasmania and 

 of the neighbouring portions of Australia, but it retreated to its 

 present confines — a circum-Polar Continent — at a time apparently 

 concurrent with the disappearance of the extensive Pleistocene ice- 

 sheets of the Northern Hemisphere. 



The existence of a great land-mass situated on the face of the 

 globe just where the sun's rays fall most obliquely has the effect 

 of intensifying the Polar conditions. This result is achieved by 

 reason of the elimination of the ameliorating influence of the ocean 

 and as a result of the acceleration of the circulation of the moist 

 atmosphere from the surrounding sea to the land, owing to the 



