THE EOCENE FLORA AND FAUNA. 285 



The London Clay at Walton is the typical stiff bluish-black 

 clay, turning brown where exposed to atmospheric agencies, and 

 containing thick bands of hard argillaceous limestone full of 

 curious vermiform concretions which stand out in relief on 

 weathered blocks. 



Plant remains were chiefly represented by twigs and pieces 

 of wood, some of which were riddled with the tubes of a boring 

 mollusc, Teredo antenautae. Of determinable vegetable remains I 

 have a very fine cone of Petrophylloides richardsoni. I also found 

 a beautiful cast in pyrites of an acorn, but although it must still 

 be in my collection somewhere, I have not yet been able to lay 

 my hands on it ; so minutely had the replacement of the organic 

 structure by the mineral taken place, that I was able to lift it 

 out and replace it in the " cup." 



The Hydrozoan Graphulavia weiheyelli occurred in abundance, 

 forming the axis of cylindrical nodules of hardened clay. 



The Crinoid Balanocrinus siibasaltiformis was the commonest 

 of all the fossils, but unfortunately I have not kept any examples. 

 I tn;st that the next time a member of the Essex Field Club 

 visits the locality, he will remember the Museum. 



The small crab Plagiolophus wetherelli is represented by a 

 complete carapace. The local barber had a lovely specimen of 

 the Eocene lobster, Hoploparia gamniayoides, on the outside of a 

 nodule of London Clay, and I myself obtained claws both of this 

 species and of H. belli. 



The Brachiopoda are represented by a single species, 

 Teyebrattilma striatula. 



Of the Mollusca, besides the Teredo antenautae already referred 

 to, I obtained an internal cast of another Pelecypod, and one of 

 a Gastropod, but they could not be satisfactorily determined. 

 The Cephalopoda are represented by the genus Nautilus of 

 which the local barber had several examples both large and 

 small. 



The Selachian (Sharks) remams were mostly in a good state 

 of pieservation and so have escaped the fate of the majority. In 

 nomenclature I have followed Mr. A. S. Woodward's " Notes on 

 the Teeth of Sharks and Skates from the English Hocene 

 Formations."' 



I Proc. Geologists' Assoc, vol. xvi. (1899). 



