264 Notices of Memoirs — The Suh-Wealden Boring. 



has yet been observed. In the Bas Boulonnais GrypJiea virgula, whilst 

 occurring all through the Kimmeridge Clay, is especially abundant 

 in the lower part. The absence of this in the boring, whilst other 

 shells are so remarkably abundant, might lead us to fear that there 

 is yet a good deal of Kimmeridge Clay to come. On the other hand, 

 it should be remembered that at Weymouth, as Mr. Bristow informs 

 me, it is the lower part of the Kimmeridge Clay which yields the 

 most petroleum ; and as we are now well down in the oil-bearing 

 beds, we may hope that the base of the clay is not far off. 



" List of Fossils from the Kimmeridge Clay of the Sub-Wealden 

 Boring : — 



Discina (^Patella) latissima. 

 Lingula ovalis. 



Area. 



Astarte Martwellensis. 



A. aliena, Phil. 



Gardium striatulum, Sow. 



C. ? sp. 



Exogyra nana, Sow. 



Lucina (? young forms of L. 



Modiola. 



Myacites. 



Ostrea deltoidea (?), Sow. 



Ostrea ? sp. 



Pecten arcuatus, Sow. 



P. (a form with coarse ribs). 



Thracia depressa, Sow. 



Trigonia. 



Alaria. 



Ammonites biplex, Sow, 

 Belemnite. 



Hyhodus (tooth). 

 Fragments of fish bones. 



"W. TOPLEY. 



According to Mr. Bristow, the Kimmeridge Clays, near Weymouth, 

 have been ascertained, by actual clitf measurement, to be 530 feet 

 thick. They are supposed to thin out towards the east, and at 

 Netherfield will probably not exceed 400 feet, of which 360 feet 

 have been already pierced. Mr. Willett states that during the last 

 quarter, gypsum beds, which would probably never have been 

 known but for this scientific enterprise, have been sought for and 

 found at Archer's Wood, on the estate of the Earl of Ashburnham, 

 who was the earliest patron and one of the most munificent donors 

 to the Fund. A shaft for verifying and working the gypsum beds 

 has also been commenced upon Mr. Egerton's estate, within a few 

 yards of our shed, just across the stream. It is a matter of con- 

 gratulation that by this discovery there has been developed for 

 Sussex a new industry, which promises to be highly remunerative to 

 all parties. 



Mr. Topley speaks of the classification of those rocks formerly 

 known as the Ashburnham beds, and which consisted of those clays 

 which formed the cliffs of Fairlight. It was at one time very 

 doubtful whether the Geological Survey should give this name to 

 the strata in the interior of the country near Battle, and when 

 the gypsum was discovered there, it decided them what to do, as 

 they did not find gypsum in the Weald proper. They resolved 

 to call the beds in the country near Battle the Purbeck beds, and to 

 keep the strata on the coast about Hastings in the Wealden, and they 

 now called them the Fairlight clays. H. B. W. 



