FOSSIL FAUNA. 127 



PLATE LIV. 



Various Species of Fossil Sea-Urchins. 



Fig. 1. A large, discoidal echinite, of the type called Clypeus or Shield-echinus, {Clypeus siuuattis, 

 of Leske,) from the Coral Rag of Oxfordshire. This species abounds in the beds of 

 this division of the Oolite in Berkshire, Wiltshire, Gloustershire, &c. 



Fig. 2. " Echinanthites orbicularis {Pypurus) of Leske." — Mr. Parkinson. 



Fig. 3. An imperfect flint cast of an echinus {Discoidea), from the South Downs. 



Fig. 4. The Helmet Echinite, {Ananchytes ovatus, of Lamarck,) from the Chalk of Kent. This is 

 a characteristic species of the white chalk, and abounds in the strata of the North 

 and South Downs. At Northfleet, near Gravesend, the quarry-men find beautiful 

 specimens. 



Fig. 5. An oval echinite (Nucleolites,) from Verona. 



Fig. 6. A portion of a very flat echinite, in which the rays or ambulacra are in a floriform 

 arrangement, {Eckinodisous bisperforatus, of Parkinson; Lobophora biperforata, of 

 Desor,) from Tertiary Strata, Verona. 



Fig. 7. A small discoidal echinite (Discoidea subuculus, of Leske,) from the upper greensand of 

 Warminster. 



Fig. 8. The floriform radiated part of the shell of an echinite (Clypeaster), from the tertiary 

 strata of Malta. 



Fig. 9. A cast in flint of part of the interior of the case or shell of an echinite. 



Fig. 10. An elegant conical echinite {Conulm albogalerus, of Leske ; Galerites, of Agassiz), common 

 in the chalk of Kent and Sussex, 



Fig. 11. View of the base of fig. 10, showing the situation of the two apertures of the shell. 



