Vol. 50.] ANNIVERSARY ADDRESS OF THE PRESIDENT. 103 



however, been already dealt with by Sir A. Geikie in his first 

 Presidential Address. Perhaps one of the most valuable lessons 

 which a study of these rocks, and of the pre-Torridonian movements 

 by which they have been affected, conveys, is to be sought in the 

 evidence thus afforded that the foliation of eruptive rocks is one of 

 the possible and even probable modes of the formation of gneiss. 

 So thought Prof. Bertrand, after his recent visit to the North-west 

 Highlands, which he regards as a district that everyone must study 

 who wishes to comprehend such matters. At this view of the casa 

 British geologists are not likely to be surprised, since the history of 

 petrology for the last seven years yields abundant proof of the 

 change which has come over men's minds with reference to the 

 origin of foliated and schistose rocks. 



There is no region, perhaps, where these views have received 

 stronger confirmation than in the limited yet classic region of the 

 Malverns. It will be convenient to consider the subject under the 

 heading ' Fundamental Rocks,' since there can be little doubt that 

 the main mass of schistose crystalline rocks in this area may be 

 regarded as of Archaean age ; although it is just possible that some 

 of the rocks subsequently placed in the ' Miscellaneous ' group 

 have as much title to be considered Archaean as those of 

 Malvern. There have been two principal competitors in this field, 

 viz., Mr. Rutley and Dr. Callaway, the former of whom has written 

 two and the latter three papers on the district. It is true that 

 Mr. Rutley has also contributed a third paper on Perlitic Felsites, 

 probably of Archaean age,from the flanks of the Herefordshire Beacon ; 

 but as the main interest of this paper relates to decomposition- 

 products, chiefly epidote with possibly a little kaolin, which have 

 been formed within the minute fissures and perlitic cracks, it need 

 not further be quoted in reference to the possible origin of the 

 Malvern crystalline rocks. 



Mr. Rutley broke ground some years ago with his duplicate paper 

 on the Metamorphic Rocks of the Malvern Hills. He first recited 

 the endeavours of Holl to demonstrate that the rocks which had 

 hitherto been regarded as ' syenite ' and supposed to form the axis 

 of the hills were in reality of metamorphic origin and pre-Cambrian 

 age. The Author restricted his observations to the old ridge of 

 gneissic ' syenite,' granite, etc., which he considered might be 

 divided into three series. The lower series, occupying the northern 

 part of the range, consists of coarsely crystalline gneissic rocks, 

 granite, ' syenite,' etc. ; the middle series of gneissic, granitic, 



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