seen more than two specimens, namely, that which 

 is in Mr. Saulier's Collection in Paris, and that which 

 adorns the present Collection. Tlie faithful repre- 

 sentation we have given of it will prove to all who 

 have seen the specimen in Mr. Saulier's Collection, 

 that ours is by far the finer, both in respect of size 

 and colour. 



In making the Catalogue we have frequently been 

 puzzled by the discrepancies between Lamarck's de- 

 scriptions and the figures to which he has referred, 

 and sometimes by his referring to figures of two very 

 difierent shells for the same species ; we have, how- 

 ever, endeavoured to ascertain, by a coinjiarison of 

 his description with the figures cited, wliidi of tlic 

 shells he meant: in some cases this has enabled us 

 to decide; in others, where we could ii<tt decide, we 

 have expressed our doubt. It will be obvious to 

 every conchological student that Lamarck's M'ork is 

 very incomplete, and that many 8j)ccics that have 

 been long well known are not to be found there ; to 

 these wc liavc given the specific names which we 

 have ascertained in otlicr uuliiors, joining tlicni to 

 their proper Lanuirckian Genera. Some of tlie ob- 

 vious modern improvements have also been adopted, 

 particularly several new genera, of wlii<h the cha- 

 racters have been published since the appearance of 

 Lamarck's Hist. Nat. ch-s Anim. sans Vert. In a few 

 instances, also, we have ventured to ciiunge the 

 places of some of the species from genera in which 

 they have been placed by mistake, to others with 

 which they accord perfectly. 



