GREENSAND FOSSILS. 191 



occur in some of the sands at Atherfield. The species is 



generally more elongated than in the individual figured. 



Venus striato-costata, PL IV. fig. 4. A small and easily 



recognised shell. 

 Venus parva, PL IV. fig. 7. In iron-stone nodules in Shank 

 lin cliff. 



Area raulini, PL IV. fig. 5. 



Perna mulleti, PI. IV. fig. 6. This large and remarkable 

 bivalve, occurs in great numbers in a thick layer imme- 

 diately above the junction of the greensand with the 

 wealden, at Atherfield and Sandown-bay. The prolonged 

 hinge-line is commonly broken off in extracting the shells 

 from their matrix, unless due care is taken. 



Thetis minor, PL V. figs. 1, 2. These are only casts in 

 ironstone, the shell having perished. They are abundant 

 in the concretions from the ferruginous sand on the top of 

 the cliff at Dunnose Point, that have fallen on the shore. 



Gryphea sinuata, PL V. fig. 3. This shell attains a large 

 size ; specimens are numerous along the shores at Shank- 

 lin, Ventnor, and in Compton-bay ; being washed out of 

 the cliffs of greensand. 



Terebratula sella, PL V. fig. 5. This shell in a very perfect 

 state is found by hundreds in the greensand at Atherfield, 

 &c. It occurs in great numbers in the greensand-pits at 

 Faringdon in Berkshire. 



Nucula scajrfia, PL V. fig. 6. This and the following small 

 shells abound in the Atherfield Crackers-rock. 



Tornatella albensis, PL V. fig. 4. 



Xalicarotundata, PL V. fig. 7. 



Pterocera retusa, PL V. fig. 8. 



Eostellaria robaldina, PL V. fig. 9. 



Cerithium turriculatum, PL V. fig. 10. 



Scaphites gigas, PL V. fig. 11. This shell attains a large 

 size ; specimens two feet long are sometimes found. The 

 collections of Capt. Ibbetson and Mr. Bowerbank contain 

 splendid examples. Imperfect specimens of the spiral 

 part have been described under different generic names. 



