56 



LOWER LIAS. 



LiTHOLOGY. 



No. ft. in. 



18. Dark-blue shale 2 



19. Hard grayish limestone 6 



20. Soft bluish shale 2 



21. Grayish-blue limestone 4 



22. Dark-gray laminated shale 4 



23. Hard blue limestone 1 



24. Gray laminated shale I 3 



25/ Grayish limestone 1 



26. Dark shale 2 



27. Thin-bedded limestone 3 



28. Thick blue limestone 5 



29. Hard fine-grained limestone 4 



30. Hard, gray, fine-grained limestone 4 



31. Hard gray limestone, forming the bot- 



tom bed 1 



Organic Remains; and the Local Names of Beds. 



Ostrea liassica and 3Iodiola minima. 

 "Six-inch building- stone." Ceromya, Modiola 

 minima, and Ostrea liassica. 



" Four-inch building-stone." Fossils as in No. 19. 

 Ichthyosaurus intermedins and /. tenuirostris. 

 "The Blue Clog," or "One-foot building-stone," 



used for steps. Ceromya, Ostrea, Modiola, and 



Rhynchonella. 

 Saurians abundant : Ichthyosaurus intermedius and 



/. tenuirostris, Pholidophorus leptocephalus, 



Agass. 

 " Gray Clog." A valuable building-stone, used for 



steps, troughs, &c. Modiola minima. 



" Three-inch blue bed." Fisli-remains, Modiola 

 minima, and Otopteris acuminata, L. & II. 



" Fire-stone.'' 



Plesiosaurus Etheridgii. (In the Jermyn Street 



Musenm ; and another now in Street are from 

 this bed.) 

 " Fire-stone, bottom bed." Plesiosaurus Hawkinsii. 



[The large Pies, tnegaceplialus, Stutch., now in 



the Bristol Institution, was obtained from this 



bed near Street.] 



The Saurian beds near Langport have likewise yielded Reptilian remains. I have 

 obtained two fine specimens of IcJdhi/osaurus intermedius and an imperfect specimen of 

 /. tenuirostris from this locality, which are now in the collections of private friends. 

 Li connexion with these Saurian beds of Somerset, it is important to note that the 

 oldest Enaliosauria of the Lias are Plesiosauri ; Plesiosaurus Hawkinsii, Owen, and 

 PL EtheriJ(/ii, Huxley, were both exhumed from the 4-inch firestone, forming the bottom 

 bed of the Ostrea series ; the remarkable Plesiosaurus megacephalus, Stutch., now in the 

 Bristol Museum, was found likewise in the firestones of a quarry near Street Foss, and 

 it will be shown in ray section of the correlative beds of this zone at Wilmcote, in War- 

 wickshire, that the fine skeleton of Plesiosaurus megacephalas contained in the Warwick 

 Museum was likewise exhumed from the " firestones " of that locality — beds which are the 

 precise equivalents of the " firestones " of Street. 



The small number of ConchiJ'era hitherto found in these beds is very remarkable. 

 Ostrea liassica, Strickl., 0. irrer/ularis, Quenst., Modiola minima, Sow., J/, jjsilonoli, 

 Quenst., Gervillia, n. sp., Anomjja, n. sp., Myacilcs, n. sp.. Area, n., sp., and Cardium, 

 n. sp., are the only species I have as yet collected from the firestone-beds. 



