Reports and Proceedings — Geological Society of London. 83 



«rosioa features of the Miocene-Pliocene Period, which have been 

 covered by only thin mantles as in Barbados, so that its life-history 

 falls into harmony with that of the other islands. In its older 

 beds it has the deep oceanic oozes as in Barbados. No volcanic 

 phenomena have been added to the features of these islands. 



II.— January 8th, 1902.— J. J. H. Teall, Esq., M.A., F.R.S., President, 

 in the Chair, The following communications were read : — 



1. "A System of Glacier-Lakes in the Cleveland Hills." By 

 Percy F. Kendall, Esq., F.G.S., Lecturer in Geology at the Yorkshire 

 College, Leeds. 



After referring to existing * extra-morainic ' lakes, such as the 

 Marjelen See and those of the Chaix Hills, the author proceeds to deal 

 with the criteria for the recognition of such lakes. These include 

 beaches, deltas, floor-deposits, and overflow-channels. Shore-scarps 

 are common in Cleveland, but beaches are rare or absent, the 

 reason being in part that stability was rarely secured owing to 

 the overflows being over soft Jurassic strata. Deltas also are not 

 common. The floor-deposit of lakes may be distinguished from 

 river-alluvia by the fact that the lamination is close and regular, 

 but, being parallel to the subjacent surface, it may be highly 

 inclined. On the other hand, alluvia are laid down on horizontal 

 surfaces, but rarely show good lamination. Overflow-channels are 

 grouped into four main types : ' direct overflows,' which trench the 

 main watershed of a country ; ' severed spurs,' across the spurs of 

 the main watershed ; ' marginal overflows,' at first merely a shelf 

 cut in the hillside, but subsequently developed into an actual gorge ; 

 and ' in-and-out channels,' or crescentic valleys excavated in the 

 face of a hill by water flowing round a lobe of ice. Such overflows 

 are independent of the natural drainage ; they have at first a slight 

 and then a steep fall, and in section they have steep sides and flat 

 floors. The meanders of the valleys and the run of the contouring 

 also possess special features, and the valleys rarely or never receive 

 any considerable tributaries. 



Evidence from borings and drift-filled channels is given to show 

 that during or before the Glacial Period the land was considerably 

 above its present level. The Glacial deposits are described in detail 

 from sections and borings, some of them carried out by the author, 

 and the assemblages of boulders are identified and classified into 

 throe chief groups — a Western group, from the Sol way, Vale of Eden, 

 Staiumoor Pass, and the Tees ; a Northern group, from the Tweed 

 and Cheviots and from Eastern Durham ; and an Eastern group, 

 from the Christiania region, the Gulf of Bothnia, and Denmark or 

 the North Sea. 



The author has been unable to detect any signs of the presence 

 of the sea in this area at any time during the Glacial Period. 

 Three main ice-masses appear to have been concerned in producing 

 the deposits : one from the Southern Uplands and the Solway, 

 joined by the local ice of the Tees ; a second originating in the 



