and Barton Clay. 249 



Natica, Ancillaria, Turritella, &c., &c. A large 

 Oyster (0. picta), various Pectens, a great Cardita (C. 

 planicosta), Cardium, Cytherea, Solen, Sanguinolaria, 

 &c., are common in England in the Bracklesham series, 

 and a foraminifer, Nummulites Icevigatus. In the 

 same set of rocks there have also been found a serpent 

 Palceophis Typhceus, 20 feet in length, and P. porca- 

 tus ; a turtle, Chelone trigoniceps ; a crocodile, Gavialis 

 Dixoni ; and a tapiroid mammal, Lophiodon minimus ; 

 and fish, including Sharks and Sword-fish. The Bag- 

 shot Sands form the highest Eocene beds of the London 

 basin. In the Hampshire basin, however, there are 

 many newer formations. 



The Barton Clay, on the coast west of Lymington 

 in Hampshire, is quite a local deposit, and both on 

 stratigraphical and palseontological grounds is assumed 

 to be the general equivalent of the clays that lie be- 

 tween the Upper and Lower Bagshot Sands. It is espe- 

 cially fossiliferous, containing a few fish, a crocodile ( C. 

 Hasting sice), and more than 200 described species of 

 marine shells. These have in general a tropical cha- 

 racter, as if in the course of time the climate of our 

 area had become warmer, due possibly to astronomical 

 causes, which I need not here stay to describe. Among 

 them are large Nummulites., various large and small 

 Volutas ( V. athleta, V. ambigua, V. luctatrix, &c.) ; 

 Murex minax, Rostellaria ampla, and others ; Bucci- 

 num, Triton, Turritella, Natica, and many more. 

 Numerous Lamellibranchiate molluscs also occur, in- 

 cluding Oysters (0. flabellula, &c.) ; Chama squamosa^ 

 Pectunculus deletus, &c. ; Area duplicata, &c. ; Car- 

 dium porulosum, &c. ; Cardita, Panopcea, Cytherea, 

 Corbula, &c , &c. Near Poole Harbour land-plants 

 occur in these strata in lenticular beds of pipe-clay, 



