﻿102 SUPPLEMENT TO THE CRAG MOLLUSCA. 



Bell (' Ann. and Mag. Nat. Hist.,' 1870) give 0. cochlear as a Cor. Crag fossil, the former 

 referring my var. spectrum to that species. 



This probably may be so. I have therefore inserted it here as a species. 



Ostrea plicatula, Gmel. Supplement, Tab. VIII, fig 10. 

 Locality. Cor. Crag, Sutton. 



I have represented a specimen of the genus Ostrea obtained by myself which varies 

 considerably from the normal condition of 0. edtdis, but it is difficult to determine the 

 limitation of a species in this variable genus ; however, if 0. cochlear be entitled to that 

 distinction, I think my present shell may have the same honour. It may possibly be 0. 

 ungulata, Nyst., but I have given to it the prior name by Gmelin. This is very variable, 

 adhering sometimes by a very small part of the shell near the umbo, but I have specimens 

 with similar rays in which the attachment of the lower valve had been effected by much 

 the larger part of the surface. It resembles, and is probably the same as 0. cristata, 

 Born (tab. 7, fig. 3), which is plicated only near the margin. 



OSTREA PLABELLULA, Lamdrck. 



Locality. Red Crag, Sutton ? 



Many years ago I noticed in the late Mr. Edward Acton's collection of shells from the 

 nodule workings in the Red Crag near Woodbridge a specimen of this species ; but I 

 have been unable since his death to find where it has gone to, or I would have had it 

 figured. It was mentioned in my paper on the extraneous fossils of the Red Crag (' Quart. 

 Journ. Geol. Soc.,' vol. xv, p. 32), as probably introduced into the Red Crag from an 

 older formation. I perceive that it is given as a species from Biot, which is classed 

 among the Upper Tertiaries, so it is not clear but that it may have lived in the Cor. Crag 

 sea. The lithological condition of the Red Crag specimen was, however, like that of 

 Roslellaria lucida and others, regarded as derivative from older Tertiaries. 



Hinnites Cortesyi, Be France. Crag Moll., vol. ii, p. 19, Tab. III. 



Localities. Cor. Crag, Ramsholt. Red Crag, Sutton, Trimley {Bell). Eluvio- 

 marine Crag, Thorpe ? 



In the 'Ann. and Mag. Nat. Hist.,' September, 1870, this shell is given by Mr. 

 Bell from the Red Crag of Trimley as Hinnites giganteus,^ in the list to Mr. Prestwich's 

 Cor. Crag paper (' Quart. Journ. Geol. Soc./ vol. xxvii, p. 139), this name is also in- 

 serted for the Crag shell by Mr. Jeffreys, and it is given in the list by Dr. P. Carpenter 



