part 4] AM) GEOLOGY OE C'OEIitS AM) ABEH.t,LEEEN> it. 545 



unfavourable for the normal type of fauna. It was thought that 

 the black shales in question were formed under these conditions. 



With regard to the advisability of using the term Ashgillian 

 in this area, it was clear that the Phillipsinella Beds contained 

 the same fauna as the Lower Ashgillian of Cautley and Coniston 

 (as described by Prof. J. E. Marr), and therefore the Berwyn 

 strata had as much right to be called Ashgillian as the beds in the 

 type-areas. 



Prof. Pugh, in reply, stated that, while many of the graptolites 

 in the black shales of the Nod (Has suggested the zone of Plenro- 

 f/raptns linearis, there occurred, towards the base of the shales, 

 Dicranograptus clingani ; and this had led him to suggest tenta- 

 tively that the shales may represent the junction between the zones 

 of D. clingani and P. linearis. With regard to the variation in 

 folding in different beds, the Nod <llas afforded ample evidence of 

 shearing .and slipping. 



