126 FOSSIL FAUNA. 



PLATE 1,111.— continued. 



The Cidaris, or Turban Echinite, belongs to the family of radiated animals, of which the 



recent Sea-urchin [Echinus spJicBra) is a well-known example. The globular shell or envelope of 



these animals is composed of numerous calcareous polygonal plates, arranged in regular and 



elegant patterns, like the lines of the meridian on a globe. These plates are externally covered 



with papilla3 of various sizes, to which spines of corresponding magnitude are articulated. In 



some of the Cidares the principal tubercles are very large, and their spines several inches in length. 



The number and variety of the animals of this family that occur in a fossil state are so great, that 



a work expressly devoted to the subject would be required to thoroughly investigate the 



characters and relations of the known species. An elementary knowledge of this class of fossil 



remains may be obtained by reference to " Medals of Creation," chap. xi. p. 240. 



Fig. 5. Part of the case of a Cidaris attached to a flint by its outer surface, surrounded by 



upwards of twenty spines ; the interior of the shell, of a light pink colour, is exposed. 



This exquisite fossil is now in the cabinet of the Marquess of ISTorthampton. " It was 



purchased by Mr. Parkinson for the sum of twenty guineas ; but this was in the 



palmy days of the study of organic remains, before the terms Geology and Palte- 



ontology were invented, and when a choice relic of " a former world" was cheap at 



any price, in the opinion of the enthusiastic collector. 



Fig. 6. A Turban Echinite {Cidaris (Hemicidaris, of Agassiz) crenularis, of Lamarck) : from the 



Coral Rag of Wiltshire. 

 Fig. 1. A siliceous cast — that is, a flint that has been moulded in the interior of the shell, and 

 received the impress of the internal structure — of " Cidaris corollaris^ of Parkinson ; 

 [Gyphosoma correlare, of Agassiz) : from Sussex. 

 Fig. 8. Cidaris with spines, from the Oolite of Stonesfield. 

 Fig. 9. A specimen of one of the Cidares with large tubercles [Cidaris coronatus, of Goldfuss) ; 



from the Coral Rag, Oxfordshire. 

 Fig. 10. An elegant chalk echinus [Cidaris Konigi, of ManteU;' Cypliosoma Blilleri, of Agassiz; 



C. granulosus, of Goldfuss) : from Kent. 

 Fig. 11. A fine species from the chalk at Gravesend [Cidaris vesiculosus, of Goldfuss). 

 Fig. 12. A peculiar type of Cidaris [Salenia scutigera, of Goldfuss), from the freestone or upper 



greensand of Warminster, Wilts. 

 Fig. 13. Another species of the same genus {Salenia stellulata, of Agassiz); from Warminster. 

 Fig. 14. An enlarged view of part of the structure around the vertex of fig. 13. 

 Fig. 15. A species of Feather-star [Comatula pectinata, of Goldfuss) ; from Solenhofen. 

 Figs. 17, 18, 19, 20. " Minute Stellitw (that is, fossU Star-fish) ; from Verona." — Mr. Parkinson. 



These are probably the bodies or disks of Ophiurw deprived of their arms. 

 Fig, 16. The nature of the specimen figured is unknown to me. 



Fossils of the South Downs, p. 189. (1822.) 



