﻿250 de. a. vattghan on the paljsontological [May 1905, 



Bristol area the germs is extremely rare before Z 2 ; Zaphrentis is 

 also much more abundant in Z x than it is in the Bristol area. 



(2) The most conspicuous instance of this small relative displace- 

 ment of corals and brachiopods is, however, to be seen in the range 

 of Caninia cylindrica in the two areas. In the Bristol area the 

 maximum of Caninia occurs above the brachiopod-facies which is 

 typical of Z 2 , and the maximum of Syringoiliyris cuspidata occurs 

 just below that of Caninia. In the Men dip area, however, the 

 maximum of Caninia is associated with a typical Z 2 facies of 

 brachiopods, and the maximum of Syringothyris cuspidata occurs 

 above that of Caninia. 



The brachiopod-progression is identical in both areas, as is also 

 the coral-progression ; but the one is slightly displaced relatively to 

 the other, as we pass from the Mendip area into the Bristol area. 

 The same phenomenon is exhibited in the position of the second 

 maximum of Caninia ; in the Mendips it takes place at the top of C, 

 in the Bristol area it occurs in S r 



The remaining areas will, for want of space, be treated very 

 shortly, and the statement that a certain zone or subzone is present 

 must be taken to imply that the assemblage of fossils by which it 

 is characterized in the Bristol area occurs also in the area under 

 consideration. 



(ii) The Weston Area. 



1. The Woodspring ridge exhibits a very fossiliferous development 

 of Z 2 , succeeded by characteristic ' laminosa-dolomites ' and i Caninia- 

 Oolite/ There is practically no difference between the fauna here 

 and in the Clevedon area. 



2. The west of the Worle ridge from Spring Cove to Knightstone. 

 The upper part of C and the Yisean, up to a high level in S 2 , 



are quite characteristically displayed. The upper part of C is little 

 dolomitized, so that it exhibits the fossiliferous character which it 

 has in the Mendips. 



Note. — From material supplied to me by Prof. C. Lloyd Morgan 

 & Prof. S. H. Reynolds when they were preparing their paper, 1 

 I came to the conclusion that both the lava at "Woodspring and that at 

 Spring Cove were poured out at approximately the same epoch; and, 

 speaking broadly, this has been confirmed by more careful examination 

 in the field. Both flows certainly took place during the deposition of 

 the laminosa-subzone. Having, however, examined the beds in situ, 

 I am now able to fix accurately the time of each flow: that at 

 Woodspring occurred in y, that is, at the very beginning of laminosa- 

 time in the Weston area, whereas that at Spring Cove occurred 

 later, but still before the close of the laminosa-age. 



The evidence for this conclusion is definite: at Spring Cove Cyatho- 

 phyllum (j) occurs below the lava, thus placing the volcanic rocks in 

 the upper part of the laminosa-subzone, whereas at Woodspring the 

 lava occurs at the y horizon. 



1 Quart, Journ. Gfeol. Soc. vol. lx (1904) p. 151. 



