298 



ON THE PERMIAN ETC. ROCKS OF THE CARLISLE BASIN. 



Discussion. 



Mr. Bauerman, having experienced the extreme difficulty of 

 understanding the rocks of this district from the obscurity of the 

 evidence, bore testimony to the great care and skill with which 

 the author had worked out such an unpromising subject. 



Prof. Judd remarked upon the great interest attachiug to the 

 outlying patch of Lias near Carlisle. The author had now, for the 

 first time, made us acquainted with the thickness of these Lias 

 strata, and proved that it exceeded 200 feet. So far as the evidence 

 went, they belong entirely to the Infralias, and the same member 

 of the Lias was also abnormally thick on the west coast of Scotland. 

 The numerous unconformities pointed out by the author as existing 

 among the red rocks below seemed to show that but little value 

 should be attached to such local unconformities in classifying the 

 strata. 



Mr. Whttaker said that his colleague Mr. H. B. Woodward pro- 

 posed to group the whole of these red rocks under the comprehensive 

 term Poikilitic, and thought that the Rhsetic beds are most likely 

 present in the area, although not seen. He spoke of the unsafe 

 character of the colour-test in classifying rocks. 



Rev. J. P. Blaeh asked as to the evidence of the existence of as 

 much as 200 feet of Lias beds belonging entirely to the lowest part 

 of the series, and as to the proofs of the existence of an uncon- 

 formity between the Stanwix Marls and the Lias. 



Prof. T. Rupert Jones protested, with reference to the use of the 

 word " Poikilitic," used by preceding speakers indicative of anti- 

 Permian views, that there had been good grounds for John Phillips 

 and others to determine and establish the Permian Series, and that 

 there were no good grounds for its being again amalgamated with 

 the overlying series. 



The President said that no evidence of the occurrence of Rhastic 

 fossils in the area had ever been found, but that possibly the 

 Stanwix Marls might have to be classed with the Rhastic Tea- 

 green Marls of the Bristol area. The Lias of Adderley was let down 

 by means of great faults below the level of the Keuper marls. 



The Author said that he advanced his classification as a purely 

 provisional one. He did not think it probable, though it is barely 

 possible, that the Stanwix Marls underlie the Lias. In classing 

 certain of these beds as Permian, Bimter, or Keuper, the author 

 chiefly desired to mark their relative positions and affinities, the 

 latter being determined by the existence or non-existence of un- 

 conformities between them. 



