620 



GEOLOGY OF THE EASTERN CORNER OF ANGLESEY. [Nov. 1896. 



Near the western end of the section the schists rise suddenly from 

 beneath these slates in a very sharp anticline (fig. 2), and disappear 

 again before rising en masse to the west, where there is a sharp fold 

 back, apparently torn 

 out into a reversed Fig. 4. — Folded bedding in pale green 



fault thrusting the 

 schists a little over n.n.w. 



fine gritty seams. 



S.S.E. 



from the west (fig. 3). 



These slates are 

 certainly unconform- 

 able to the green 

 schists. Powerfully 

 as they are folded, 

 they are not in the 

 least affected by the 

 extreme and involved 

 contortions of the 

 schists, which are 

 clearly seen to be trun- 

 cated against their 

 base. Their micro- 

 scopic structures are 

 also entirely different. 



Again, the slates themselves appear to be, not a lower part of 

 the Ordovician Series, but part of some older group separated from 



In cliff above cave, fig. 6. 



[About h natural size.] 



Pig. 5. — Grit with sponge-spicules, Car eg Onen. 



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SX': 



X 40. 



that series by another unconformity. Indeed, I think that this 

 junction, rather than that between the slates and schists, must be 



