46 Mr. De la Beche on the South Coast of England. 



cimens represented Plate VII. figs. 2. and 3, are from the collection of Pro- 

 fessor Buckland^ and were obtained from the lias of Axminster : fig-. 2 being 

 from the vvhite^ and fig. 3 from blue lias. 



Many varieties of Ammonites are found also at Lyme, the most perfect oc- 

 curring in the hard lias limestone or in nodules in the marly strata : these no- 

 dules are frequently spherical, and of large size. Among the Ammonites are 

 the following : 



Ammonites stellaris *. Ammonites Brookii. 

 ellipticus. Greenovii. 



obtusus. Henleii. 



communis. Loscombii. 



discus. Birchii. 



armatus. Konigii. 



The Nautilus striatus is the only species of that genus that I have yet ob- 

 served in the lias near Lyme. Among the univalves are also the following: 



Trochus anglicus. Cirrus 



imbricatus. Melania 



Helicina expansa. 



The Gryphaea incurva, though generally common in liasf , is not so much so 

 near Lyme. 



Terebratulas occur in abundance, with many other bivalves. Among which 

 are, Aviculainaequivalvis^ModiolaScalprum, Pinna ,' Plagiostoma gigantea. 



Small casts of turbines are found composed of iron pyrites, which enters 

 largely into the composition of many fossils of the lias, particularly the Ammo- 

 nites. 



Red Marl, Sandstone, and Conglomerate. 



This formation occupies a large portion of the coast of Devonshire ; it first 

 appears, on the part of the coast now under consideration, beneath Dowlands 

 near Axmouth, rising from below lias ; it forms some low cliffs near Seaton, 

 and from thence, with the exception of White Cliff and Beer Head, it consti- 

 tutes the lower part of all the cliffs to High Peak, on the west of Sidmouth : 

 proceeding westward, it forms the entire cliffs as far as Babbacombe Bay, where 

 it rests upon limestone. The conglomerate at Teignmouth includes large 



* The names here given are those of Sowerby's Mineral Conchology. 



t The lias is generally known in France by the name of Pierre « GryphUe. 



