and its Claim to rank with existing Species. 39 



quoted, Parkinson observes, " A very fine fossil shell, bearing 

 much the form of this volute, is found in some parts of York- 

 shire; I believe in the neighbourhood of Whitby. This shell 

 is so perfect, and its colours are so well preserved, that a 

 specimen of it having fallen some years since into the hands of 

 Mr. George Humphries, he was deceived into the opinion of 

 its being a dead shell ; and being satisfied that it was of a 

 species which was entirely unknown, he cleaned and polished 

 it as a recent shell, and was not undeceived, until, at a sub- 

 sequent period, he saw another specimen, by which he was 

 enabled to ascertain its being really a fossil." 



So long a time has elapsed since the above was written, that 

 I have not been able to gain any more information respecting 

 the shell here spoken of; but I can only conjecture, from Mr. 

 Parkinson's account, that it was one of these fine volutes 

 thrown on shore at Whitby. The fact is certainly highly 

 interesting, considering the great distance between the two 

 localities, unless we suppose that the shell was transported from 

 the Suffolk to the Yorkshire coast. Mr. Humphries is not the 

 only individual who has been misled in this way ; a similar 

 instance has come under my own observation ; and, indeed, 

 some of these shells have such a recent character about them, 

 that a naturalist totally ignorant of the species indigenous to 

 the British seas might perambulate our eastern coast and 

 meet with a specimen of the Voliita Lamberti without sus- 

 pecting it to be other than a dead shell of a living mollusc. 



Now, it is very possible that those shells, which have 

 undergone so little alteration in character, may have been 

 removed from the crag before the process of mineralisation 

 had taken place to any considerable extent; or we may 

 imagine that there existed a comparatively recent fossiliferous 

 stratum in which this particular species was abundant, and of 

 which all traces are now entirely destroyed. Without enter- 

 ing largely into details to show the plausibility of the latter 

 suggestion, I may remark that, from a careful examination of 

 the deposits upon our eastern coast, I anticipate a consider- 

 able change in the opinions which geologists have usually 

 entertained respecting them, when their history shall have 

 been more fully investigated. 



The tertiary shells brought from Suffolk and the neigh- 

 bouring counties have so invariably gone under the appel- 

 lation of u crag fossils," that it is no very easy matter for a 

 geologist who has not personally examined the numerous 

 localities in which they occur, to divest himself of the im- 

 pression that they all belong to one definite deposit. 



The shells figured in Sowerby's Mineral Conchology were 



d 4 



