336 



ON THE BOCKS OF SAEK, HERM, AND JETHOXJ. 



Prof. Bonnet, in reply, said he considered glaucophane merely a 

 peculiar variety of hornblende. It would require very strong evi- 

 dence to convince him that sandstones and similar rocks did ever 

 pass into serpentine &c. With regard to Mr. Rutley's remarks, he 

 could see no evidence in Brittany of important disturbances from 

 Cambrian times till after the Carboniferous era. The questions 

 raised by Mr. Hill had been treated in the paper ; the arkose-like 

 rock turned out to be gneiss clearly crushed in situ. He agreed with 

 Dr 6 Hicks that the appearances of false-bedding in metamorphic 

 rocks were of doubtful origin, but in some cases other explanations 

 presented great difficulties, and sedimentation of some sort was pro- 

 babty to be detected in Archasan rocks. 



Mr. Hill said the appearance that he referred to false-bedding 

 occurred, not in gneiss, but in the overlying hornblende-schists. The 

 possibility of these hornblende-schists being tuffs had occurred to 

 him, but he had not been able to discover any evidence. 



