11 



adherent to the shell, appears to be of the same species with the last 

 fossil. 



As far as the characters can be traced, on the inside of the shell, it 

 appears, that to this species the specimen, Plate I. Fig. 5, is referable. 

 This extraordinary specimen, in which so rnany spines are seen im- 

 bedded in the flint, was considered as one of the most splendid fossils in 

 the Leverian Museum. 



Cidaris subangularis, ofLeske, Kleinii, Tab. in. C. D. does not appear 

 to be known as a fossil. Cidaris fenestrata, of Leske, Kleinii, Tab. iv. 

 A. B. he thinks, is the analogue of the echinite figured by Scilla, Tab. xi. 

 No. 1, Fig. 2; and by Walch, PI. E. i. a. 1. The Echinus of Klein, 

 T. iv. c. D. is considered by Leske as referable to E. lucunter, of Lin- 

 naeus. He names it, therefore, C. lucunter; and observes, that it is 

 rarely seen petrified: he however believes the fossil echinus, figured 

 by Morton, Nat. Hist, of Northumberland, P. x. F. 2, to be of this 

 species. 



Echinites ovarius, Langii, is a small fossil, in which the characters of 

 the species 'are discoverable. It is figured by Plot, Hist, of Oxfordshire, 

 Plate v. Fig. 6, and copied by Lister, de Lap. turbin. Fig. 24. Lhwydd 

 has also given a figure of this fossil, Lithophylacii Ichnogmph. Tab. ix. 

 Fig. 940. 



Small specimens, of an elliptical form, are found in the Wiltshire 

 chalk-pits, which appear to possess the characters of C.fenestrata, of Leske 

 and of Klein, and which are figured by the latter, Tab. iv. A. B. But 

 the echinus, of which three specimens are represented by Klein, Tab. v. 

 a, b, c, named C rupestris by Leske, has perhaps an equal claim to be 

 the analogue of this Wiltshire echinite, the difference not being ascer- 

 tainable; but the agreement is by no means sufficient to warrant their 

 being assumed as of the same species. 



C. calamaris araneiformis, stellata, radiata, violacea, do not appear to 

 have been remarked in a mineralised state. C. circinnatus is only known 



