80 SUPPLEMENT TO THE CRAG MOLLUSC A. 



Tab. VII, fig. 10, called L. striatula, which, however, I think is also different from the 

 Crag shell. Lacuna cliona, Raincourt and Munier, ' Journ. de Conch./ vol. xi, p. 201, 

 PL VII, fig. 1, is a similar Eocene fossil with a reticulated surface ; this group might, I 

 think, be separated from Lacuna, the only resemblance to which is the elongated 

 umbilicus. Fig. 23 of Supplement Tab. V was engraved under an impression I had 

 that it might be Lacuna quadrifasciata. It, however, differs so little from some of the 

 least elongated forms of Littorina suboperta, that it may be an immature form of that 

 shell. 



Lacuna vincta, Mont. Crag Moll., Appendix, p. 316, Tab. XXXI, fig. 13. 



Localities. Fluvio-marine Crag, Bramerton. Post Glacial, March, and Kelsea Hill. 



This shell seems to be confined to the Fluvio-marine Crag (where, according to Mr. 

 Reeve, it is rare) and not to have occurred in any other Crag, or East Anglian Glacial bed. 

 It is abundant and in good preservation in the March Gravel, and is given by Mr. 

 Jeffreys as abundant at Kelsea Hill. 



Lacuna crassior, Mont. ? 



This shell is given as occurring at Kelsea Hill, by Mr. Jeffreys, in ' Quart. Jour. 

 Geol. Soc.,' vol. xvii, p. 450, but he is silent as to it in his ' Brit. Conch.' I insert it, 

 therefore, with doubt as an East Anglian fossil. 



Trochus turgidulus ? Brocchi. Supplement, Tab. V, fig. 8. 



Trochus turgidulus, Broc. Conch, foss. Subap., vol. ii, p. 353, t. v, fig. 16, 1814. 



Alt. \ of an inch. 



Locality. Coralline Crag, Sutton. 



Two small specimens found by myself are here referred with doubt to the above- 

 named species ; they differ from T. Montacuti in having a sharper angle to the lower part 

 of the volution, and they have been somewhat abraded, by which a great part of the 

 outer coating has been removed, obliterating some of its character. They are smaller than 

 the representation by Brocchi, but they may not be full grown ; they resemble the figure 

 by Dubois, ' Coq. Foss. Volh. Pod.,' PL II, figs. 29, 30, but are less strongly striated. 

 It is, however, an unsatisfactory identification. 



