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PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Feb. 18, 



of Pentacrinus and the spines of Cklaris contribute largely to make 

 up the bed. Cidaris Edwardsii, Wright, a species very frequent in 

 the Lower Lias, occurs here. 



Pentacrinus Johnsonii, Austin. 



Cidaris Edwardsii, Wright. 



Crania. 



Terebratula cornuta, Sow. 



numismalis, Lam. 



Rhynchonella furcillata, Thcod. 

 Avicula novemcosta, Brown. 

 Lima pectinoides, Sow. 

 Hinnites velatus, Golclf. 

 Modiola. 



Hippopodium, young. 

 Cuculhea elongata, Sow. 



inajquivalvis, Gold/. 



cancellata, Phill. 



Sanguinolaria vetusta, Phill. 

 Cardinia, sp. 

 Pholadornya, sp. 



Nucula aurita.. Quenst. 



Unicardium cardioides, Phill. 



Lucina. 



Astarte. 



Pullastra. 



Venus pumila?, Ojppel. 



Isocardia. 



Pleurotomaria anglica, Sow. 



araneosa, Dcsl. 



expansa, Sow. 



Nerinaea. 



Cerithium. 



Chemnitzia. 



Ammonites Thouarsensis, D' Orb. 



margaritatus, Montf. 



Belemnites clavatus, Blainv. 

 Teeth of Hybodus. 



5. The Starjish-bed. — Besides the Ophioderma Egertoni, Broderip, 

 this stone affords a closely allied species, or variety, 0. tenuibrachiata , 

 Forbes. These Echinoderms are collected, as I have already stated, 

 from the under side of the large blocks ; in reality the layer beneath 

 which they occur is but a portion, a few inches thick, of the entire 

 stone, and this portion is a more pure sandstone than the part above. 

 As far as one can judge, the thin deposit of purer sand is as local as 

 the occurrence of the imbedded Starfish, and hence the two pheno- 

 mena appear attributable to the same cause. This consideration, the 

 peculiar situation of the Echinoderms, and the positions in which 

 they occur in the stone, lead me to imagine that we have in this 

 case a true instance of a sudden and accidental deposit and destruc- 

 tion of life, in contradistinction to the gradual and regular mode in 

 which most geological masses were accumulated. 



6. The Grey and Brown Sands with Nodules. — In these we find 

 here and there a considerable number of organic remains ; in some 

 places, lumps composed chiefly of the joints of the stems and arms of 

 Pentacrinus Johnsonii, Austin ; in others, masses of PhynchoneUaz of 

 small size. Intermingled with these are small Gasteropoda and Con- 

 chifera, together with fragments of larger shells. The latter, such 

 as Gryphcea Maccullochii, Sow., and Pecten cequivalvis, Sow., occur 

 very perfect and fine in these sands. Plicatula sjmiosa, Sow., which 

 is found in every collection of fossils from the Belemnite-beds up- 

 wards, is here abundant and fine. 



In the topmost layer of the nodules, or the " Margaritatus-stone," 

 Ammonites margaritatus occurs very large, and occasionally well 

 preserved ; as is also A. fimbriatus, with which it is associated. 

 From the overlying blue marl I have scarcely seen a fossil, so that 

 I cannot say whether it belongs palseontologically to the sands below 

 or to those above. 



Terebratula cornuta, Sow. 

 quadrifida. Lam. 



Khynchonella tetrahedra. 

 Lingula Beanii, Phill. 



Soiv. 



