144 PROCEEDINGS OP THE GEOLOGICAL SOCIETY. [Aug. 1 894, 



The List of Donations to the Library was read. 



The following communications were read : — 



1. ' Mesozoic Rocks and Crystalline Schists in the Lepontine 

 Alps.' By T. G. Bonney, D.Sc, LL.D., F.R.S., F.G.S., Professor of 

 Geology in University College, London, and Fellow of St. John's 

 College, Cambridge. 



2. 'Notes on some Trachytes, Metamorphosed Tnffs, and other 

 Rocks of Igneous Origin, on the Western Flank of Dartmoor.' By 

 Lieutenant-General C. A. M s Mahon, F.G.S. 



The following specimens were exhibited : — 



Rock-specimens and microscope-sections, exhibited by Prof. T. G. 

 Bonney, D.Sc, LL.D., F.R.S., F.G.S., in illustration of his paper. 



Rock-specimens and microscope-sections, exhibited by Lieut.- 

 General C. A. M c Mahon, F.G.S., in illustration of his paper. 



Specimen of Ecca Conglomerate from near Grahamstown, Cape 

 Colony, exhibited by Dr. J. W. Gregory, F.G.S. 



April 25th, 1894. 



Dr. Henry Woodward, F.R.S., President, in the Chair. 



John Charles Burrow, Esq., Trelowarren Street, Camborne, 

 Cornwall; and Charles Davison, Esq., M.A., 373 Gillott Road, 

 Birmingham, were elected Fellows of the Society. 



The List of Donations to the Library was read. 



Mr. A. R. Sawyer, referring to specimens exhibited by him from 

 the Transvaal, Orange Free State, Cape Colony, Mashonaland, and 

 Matabeleland (the last mentioned collected during the recent war), 

 remarked that gneisses and gneissose granites cover a large portion 

 of Mashonaland, together with patches of schistose rocks and 

 a few stratified rocks. He drew attention to the fantastic shapes 

 assumed on weathering by the granitic gneiss, which he considered 

 solely due to atmospheric agencies, and not to ice-action or to the 

 effects of submersion. 



The schistose rocks are, for the most part, sheared and altered 

 igneous masses. There are numerous examples of dolerites and 

 epidiorites passing into hornblende-schists, and of more acid igneous 

 rocks. Masses of magnetite occur in various parts of Mashonaland, 

 and serpentinous rocks (which probably owe their origin to the 

 alteration of peridotites) in the N.W. corner of the Victoria Gold- 

 field. 



