11 
The very uncommonly perfect specimen, from Stunsfield, Oxford- 
shire, Plate I. Fig. 8, in which a considerable number of spines 'are 
still 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 many spines are seen im- 
bedded in the flint, was considered as one of the most splendid fossils 
in the Leverian Museum. 
Cidaris suhangularis, of Leske, Kleinii, Tab. hi. c. d. does not 
appear to be known as a fossil. Cidaris fenestrata, of Leske, Kleinii , 
lab. iv. a. b. he thinks, is the analogue of the ecliinite figured by 
Scilla, Tab. xi. Ao. 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 Linnaeus. 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 Ox- 
fordshire, Plate v. Fig. 6, and copied by Lister, de Lap. turbin. 
Fig. 24. Lhwydd has also given a figure of this fossil, Lithophylacii 
Ichnograph. 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 ascertainable ; 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 
