DESCRIPTION OF THE PLATES. 



PLATE IV. 



Fig. 1. Clavated spines of an echinus attached to the shell, imbedded in chalk. 



2. A long spine of the species Cucumerina, attached to a mammillated echinite. 



3. Cylindrical denticulated spines, with the shell in chalk. 



4. A fossil echinital spine, resembling a belemnite. 



5. A fossil spine, named Bacolo di Santa Paulo by Scilla. 



6. A knobbed cucumerine spine. 



7. A cast of Echinanthus altus from Malta. 



8. A cucumerine spine. 



9 An echinital spine of the species glandaria. 



10. A cordated echinite from Verona. 



11. An echinital spine of the species glandaria , formerly called petrified Olives, 

 1 2. A curious flat serrated spine from Verona. 



13. A sulcated fossil from Shepey, apparently an echinital spine. 



14. An echinital spine of an uncommon character, bearing a resemblance to the 



belemnite. 



15 



..Varieties of the cucumerine species. 

 17. ' 



18. 



) 



19. A fossil spine, in chalk, possessing the structure of a belemnite. 



20. A mammillated echinite from Wiltshire. 



21. Clavated spines attached to the shell, imbedded in flint. 



PLATE V. 



Fig. 1. A fossil cone from Verona. 



2. A minute silicious rostellarite from Devonshire. 



3. Part of an uncommon fossil shell, supposed to resemble a patella in some of its 



characters. 



4. Auricula ringens, completely silicious. 



5. Chiton octavalvis, with magnified figures of adherent serpulae. 

 VOL. III. 3 O 



