282 Reports and Proceedings — 



fordshire Beacon are chiefly gneissic : the eucrite-basalt occurs at a 

 buttress of the hill. The pegmatite of Swinyard's Hill has apparently 

 been faulted into its present position. South of Midsummer Hill 

 fine-grained gneissic rocks, quartzite-schists, etc., are met with. 



There is no reason to suppose that the alteration of any ordinary 

 sedimentary rocks could have resulted in such a vast amount of 

 hornblende as is found in these gneisses. The gneissic rocks of the 

 Malvern Hills may be composed of the detritus of eruptive rocks. 



The rocks of the Malvern Hills show in their structure but little 

 resemblance to the foliation induced by shearing, the crystals seldom 

 exhibiting any marked lenticular form, while there is but little like- 

 ness to the pseudo-fluxion structure described by Lehmann, etc. 



The author. concluded that the rocks of the Malvern Hills represent 

 part of an old district consisting of plutonic and, possibly, of volcanic 

 rocks associated with tuffs, sedimentary rocks composed mainly or 

 wholly of eruptive materials, and grits and sandstones ; that the 

 structural planes in these rocks (sometimes certainly, at others 

 possibly) indicate planes of stratification, and that the foliation, in 

 many cases if not in all, denotes lamination due to deposition either 

 in water or on land surfaces, probably more or less accentuated or 

 altered by the movements which produced the upheavals, subsidences, 

 and flexures prevalent in the range. 



2. " On the alleged Conversion of Crystalline Schists into Igneous 

 Eocks in Coimty Galway." By C Callaway, Esq., D.Sc, F.G.S. 



This paper was an inquiry into the theory, held by many Irish 

 geologists, that granite and other igneous rocks are the last term in 

 a progressive series in the metamorphism of aqueous sediments. 

 The evidence collected by the author was regarded as entirely hostile 

 to this view. In Knockseefin, the typical section, he found diorite 

 intrusive in gneiss and granite intrusive in the diorite, but no passage 

 between any two. The igneous veins sometimes displayed a foliated 

 structure. At Shaunarea the phenomena were similar ; but the 

 granite in contact with the gneiss was much crushed and decomposed. 

 In the region south of Glendalough the intrusion of granite in 

 diorite and schist gave rise to the peculiar mixtiires which had been 

 described as " metamorphosed conglomerate." The granite was 

 intruded along the joints of the diorite, sometimes separating the 

 joint-blocks from each other, and completely enclosing them. It 

 was noticed that when schists were penetrated by granite isolated 

 folia often retained their parallelism, and this was accounted for 

 partly by the slowness of the intrusion, partly by regional pressure. 

 Even when mere flakes of the schist were enclosed in granite there 

 was no passage between the two. The granite, both in masses and 

 veins, was often foliated, but the blocks of included diorite were not ; 

 and this seemed to suggest that the foliation of the granite was 

 acquired before complete congelation of the larger masses. There 

 was also a foliation concentric to included blocks of diorite. 



At the town of Galway the " metamorphic sedimentary " rocks 

 were a coarse-grained hornblendic gneiss of Hebridean aspect, and 

 in some parts of it was a structure similar to that of the " metamor- 



