256 POSTSCRIPT. 



Cardium edule. p. 30. 



Variety D. With one of the valves larger and inclosing 

 the other within it, the beak curving over it. 



Specimens of this singular variety we observed in the 

 cabinet of Mrs. C. W. Loscombe, of Exmouth. 



Cardium aculeatum. p. 28. 



Walker, f. 83, 84. The very young shell. 



Opportunities of comparing these minute shells, the 

 Cardium muricatulum of modern authors, from the sands 

 of Torbay, with the C. aculeatum in its several stages of 

 growth, incline us to think they are of the same species. 

 They are of a pale yellowish color, semitransparent, with 

 the cartilage side somewhat angular and truncate, and 

 round the margins and at the sides are clothed with minute 

 spines. Our references therefore of Walker's figures to 



C. medium should be removed. 



Dentalium eburneum. p. 37. 



This and our D. politum, p. 38, do not correspond with 

 the characters of the Linnean species under these denomi- 

 nations, and we must therefore consider them as distinct 

 and nondescript ; suggesting that the former be altered to 



D. album, and the latter to D. Iceve. 



Helix Ericetorum. p. 49. 



Da Costa, pi. 4. f. 8. 



Lepas cornuta. p. 73. 



Some clusters of what appeared to be of this species 

 were lately gathered from the bottom of a vessel, in Ex- 

 mouth. They were entirely of a dusky-brown color : the 

 mouth in opening wide-oval, slightly cloven at the top, with 

 a tubercular projection on each side the cleft, and on the 

 left-hand side, below the tubercle, are several irregular flat 

 projecting foliations, v. v. 



Lepas dentata. p. 71- 



We have lately taken large masses of the several varie- 

 ties of this shell, and are fully convinced that they all be- 

 long to L. anserifera. Every conchologist knows the dif- 

 ficulty of exact discrimination between these two species : 



but 





