Correspondence — T. E. Knightley. 333 



of percussion have been found in all the gravels except the oldest. 

 The value of these flakes as evidence is disputed. 



4. " The Globigerinn-m&r\s of Barbados." By G. F. Franks, 

 F.G.S., and Prof. J. B. Harrison, M.A., F.G.S. With an Appendix 

 on the Foraminifera by F. Chapman, F.R.M.S., A.L.S. 



After a reference to previous publications on the island by one of 

 the authors and Mr. Jukes-Browne, an account is given of the 

 tectonic structure of Bissex Hill, on which the principal exposures 

 of the Globigerina-maTl occur. Five faults are described, four of 

 which cut all the rocks, while the fifth disturbs the Scotland Beds 

 and the Oceanic Series, but leaves the overlying Globigerina-marl 

 undisturbed. 



The general succession is as follows : — The Scotland Beds are 

 overlain uncouforinably by the Oceanic Series, which shows the 

 usual succession from chalks to calcareo-siliceous beds, and in places 

 to the upper chalks, the overlying red clays being absent. Then 

 follows unconformably a detrital bed of GIobigerina-mgiYl containing 

 rolled pebbles of various parts of the Oceanic Series, especially the 

 chalks, and inclusions of clay presumably from the Scotland Beds. 

 The bed is followed by buff marls, granular in appearance, and this, 

 again, by marls and limestone, in the upper part of which Globi- 

 gerincB die out and are replaced by Ampliistegina and fragments of 

 lamellibranch shells. The whole succession is about 90 feet in 

 thickness, and the beds pass up into basement-reef rocks without 

 coral, and coral-rock. 



Somewhat similar rocks were met with in a shaft at Bowmanston, 

 and they probably occur in other localities. The presence, succession, 

 and relations of these rocks enable the authors to draw conclusions 

 as to the history of the island. 



In the Appendix a list of 146 species of foraminifera is given : 

 15 of these occur only in strata ranging from the Cretaceous to the 

 Pliocene Period. The rocks bear some resemblance to the lime- 

 stones and marls of Malta and to the Globigerina-heds of Trinidad ; 

 the recent foraminifera indicate that the deposit was formed at 

 a depth of about 1,000 fathoms and at some distance from land. 



cozRiiESiPOisrjDiEn^oiE. 



EBBING AND FLOWING WELLS. 



Sir, — At the meeting of the Geological Society of London, on 

 April 20th, 1898, were read notes on the ebbing and flowing well 

 at Newton Nottage, Glamorganshire, by Mr. Madan, M.A., com- 

 municated by Mr. A. Strahan, M.A. 



The well lies about 500 yards from the sea, with sandhills 

 between, and in the neighbourhood of a range of Carboniferous 

 Limestone, whilst the same formation crops out in the sea at half- 

 tide level. At the shore junction of conglomerate and limestone 

 numerous springs occur, and it is in this conglomerate that the well 

 is sunk. After many observations, the author has constructed 



