Reports and Proceedings — Geological Society of London. 281 



Geological Society of London. 



I.— April 6, 1887.— Prof. J. W. Judd, F.E.S., President, in the 

 Chair. — The following communications were read : — 



1. " On the Eocks of the Malvern Hills." Part 11. By Frank 

 Eutley, Esq., F.G.S. 



The details of the microscopic examination of the rocks constituted 

 the principal part of the present paper. The author finds that the 

 truly eruptive rocks are more plentiful in the range than he was at 

 first led to suppose. In all 33 rock-specimens were described, and 

 in some cases Mr. Timmins's analyses were quoted. The author 

 commenced with the rocks of the North Hill and concluded with 

 those of the Eaggedstone Hill. Eocks between a little south of the 

 summit of the Worcestershire Beacon on to Wind's Point, those of 

 Midsummer Hill, and those of Keys Hill were not collected. The 

 following; are the sreneral results : — 



In the first instance a separation must be effected of rocks showing 

 foliation or lamination, or of which the origin has been sedimentary, 

 from those which show no such structure, and which must be 

 regarded as eruptive : there is, in fact, a banded and an unhanded 

 series. The gneisses are altered volcanic tufi's or sedimentary rocks 

 of eruptive material derived from the disintegration of rocks of 

 dioritic or syenitic character. 



The rocks of the North Hill, as maybe gathered from the tabular 

 classification, are truly eruptive in many cases ; whilst the foliated 

 varieties are made up of the debris of rocks rich in hornblende, 

 which may have had an eruptive origin. The rocks of the Here- 



