Part of Carnarvonshire. 



15 



and Geikie 1 maintained that the conglomerate merely marked a phase 

 in the Cambrian succession, and agreed with Ramsay that the base of 

 the Cambrian succession was not exposed in Carnarvonshire. Blake 

 also had previously maintained this latter view, 2 but at a later date 

 he went so far as to suggest that the Moel Tryfan conglomerate- 

 lying directly on the volcanic series — was of post-Cambrian age. 3 



The view generally held nowadays is that although no uncon- 

 formity has been shown to exist anywhere along: the ridge.yet the 

 volcanic series is Pre-Cambrian and the conglomerate is basal 

 Cambrian. 



GEOLOGICAL MAP OF 

 A PART OF SOUTH WEST 

 •> CAERNARVONSHIRE. 



MAP IE. r^Ss^s 



finite* / 

 Sw-vey Soundorv of RhyoUttc Series. 



2. Particular Area, including Cil-y-Coed, Craig-y-Dinas, and 



Bryn-mawr. (See Map II.) 

 Turning now to the literature relating to the district immediately 

 south-west of the main ridge, one finds that very little attention has 

 been paid to the ground. The Survey memoir of 1866 only refers to 



1 Ancient Volcanoes of Great Britain, vol. i, pp. 160, 163, 1897. 



2 Q.J.G.S., vol. xliv, p. 288, 1888. 



3 Geol. Assoc. Eeport of Blake's Caernarvonshire Excursion. 



