^^^' 55'] TORSION-STRUCTURE OF THE DOLOMITES. 633 



My grateful thanks are especially due to Prof. Lapworth, who, 

 with his unfailing kindness to workers in geology, has freely ex- 

 tended to me advice and encouragement. The reader will have 

 gathered for himself to what extent the general inferences drawn by 

 Prof. Lapworth accord with my own detailed field-work ; and it was 

 a matter of especial gratification to me when he consented to read 

 this paper on my behalf at the present meeting of the Geological 

 Society. 



Einally, my cordial thanks are also due to Prof. Watts for his 

 kindness in communicating this paper, as well as for his careful 

 microscopic examination of the specimens of igneous rock brought 

 by me from various localities in Enneberg. 



EXPLANATION OF PLATE XL. 

 General Geological Map of the Sella Massive and Enneberg, on the scale of 



, or about 1*267 inches to the mile. 

 It will be noted that a small area north-east of Vallon, left white in error, 

 should have been shaded as Schlern Dolomite. 



Discussion. 



Prof. BoNNEY said that he had not visited the region since 1880, 

 and then had not passed over the precise area examined. The 

 hypothesis advanced by the Author explained many difficulties, but 

 he had doabts about the date assigned to the eruptions, for he felt 

 convinced that these were of Triassic age. Also he much doubted 

 the ages assigned to the movements, namely, whether the east- 

 and-west foldings were the earlier. He had pointed out more than 

 ten years ago that in the Alps, most strongly in the eastern 

 and western portions, foldings could be traced from north-north- 

 east to south-south-west modifying the east-and-west foldings, 

 which, however, had an even boundary on the north. The former 

 foldings agree with post-Carboniferous and pre-Mesozoic folds, of 

 which he gave instances. The Alps, in fact, were regions of 

 repeated movements, and greatly as he was impressed by the ability 

 of the paper, he must suspend his judgment till he could read and 

 consider it thoroughly. 



Prof. SoLLAs expressed his admiration of this brilliant and solid 

 piece of work, which had been rendered intelligible to the meanest 

 capacity by the lucid explanation of Prof. Lapworth. In the 

 course of the exposition we had witnessed with mingled feelings 

 the dissolution of Eichthofen's coral-reefs, as they disappeared in a 

 chaos of thrusts and overfolds, and the evolution of a new system 

 which was more wonderful than the old. The structure of the 

 Dolomites still seemed to the speaker suggestive of coral-reefs, which 

 could not have been mere fringes, but were comparable to barriers 

 and atolls ; and it was possible that in the Tyrol we were confronted 

 with mixed phenomena. If so, the disturbances of the district could 

 not be regarded as affecting a homogeneous system of sheets, and 



