9-i Reports cO Proceedings — Geological Society of London. 



difference in mineral products. The area of the Eenom Anticline 

 coincides with the ' gold-belt ' of the Peninsula. The products of 

 the Main Range Anticline are tin and wolfram. 



Tertiary Coal-measures, unconformable on the Gondwana rocks, 

 are known in Selangor. Their exact age cannot be determined, 

 since the flora resembles the existing jungle flora; and the same 

 may be said of floras in Borneo Coal-measures that are believed to 

 date back to the Eocene Period. An arrangement based on the 

 percentage of moisture in the coal, however, points to the possibility 

 of their being Miocene. 



Evidence has been found in the Peninsula supplementing the 

 biological evidence described by Dr. A. E.. Wallace of changes in 

 the Archipelago in Tertiary times. When the land-connexion that 

 allowed the migration of the fauna of the Archipelago from the 

 north was destroyed by submergence, the subsidence continued until 

 the Peninsula became an island or group of islands. Subsidence 

 then gave place to elevation, which restored the Peninsula and is 

 continuing at the present day. 



Interesting recent deposits are deposits of lignite in ' cups ' formed 

 by solution in the limestone of the Raub Series, and torrential 

 deposits made up of ' core-boulders ' derived from weathered granite. 



2. " On a Mass of Anhydrite in the Magnesian Limestone at 

 Hartlepool." By Charles Taylor Trechmann, B.Sc. (Communicated 

 by Professor E. J. Garwood, M.A., V.P.G.S.) 



The harbour of Hartlepool owes its existence to the erosion of 

 a mass of anhydrite of great thickness, proved by boring and other 

 evidence to exist in close proximity to the Upper Magnesian Limestone 

 upon which the towns of Hartlepool and West Hartlepool are built. 



The anhydrite is shown to be included in, and to represent the 

 time-equivalent of part of, the Middle and the greater part of the 

 Upper Limestones. The contrary view, that the anhydrite helongs 

 to the overlying red beds here faulted down, is shown to be erroneous. 



The former presence of sulphates in the Magnesian Limestone is 

 discussed. This formation, wherever protected by overlying com- 

 paratively impervious beds, proves to be more or less gypsiferous 

 throughout its thickness. Evidence is brought to show that very 

 large quantities of anhydrite were originally deposited with the 

 Magnesian Limestone, the subsequent hydration and removal of 

 which is chiefly responsible for the collapse, degradation, brecciation, 

 and other alterations that are such obvious features of the formation 

 in its present condition. 



The distribution of oi'ganisins in the Magnesian Limestone was 

 largely influenced by the qutintity of sulphates present in the 

 surrounding water. The Shell Limestone is shown to be a chain 

 of reef-knolls, in the building up of which a limited number of 

 forms take part, probably induced by current action in the Permian 

 sea and lying more or less parallel with the old Permian shore-line. 

 The increasingly unfavourable conditions prevailing towards the top 

 of the Shell Limestone bring about a dwarfing and gradual extinction 

 of the typical Shell Limestone fauna. 



