PLATE CXLXI. 



The shell before us presents one of those anomalies which often- 

 times interfere with and distract the arrangements of those naturalists 

 who, however proficient in other respects, are too prone to indulge 

 in the formation of new genera, where nature seems herself to point 

 out the propriety of being less diffuse ; and not unfrequently it may 

 be added, evince the necessity of closer circumspection. We are 

 led to this reflection, from tracing the various changes that have 

 taken place among naturalists in the generical disposition of the 

 shell, which we conceive to be a near analogy to that selected in this 

 place for observation. The shell adverted to is one of the largest 

 and most striking in its appearance of the tribe of land shells with 

 which we are acquainted ; a shell known from the time of Bonanni, 

 Lister, and Seba, and which yet has never been disposed with a 

 sufficient degree of precision in any of the genera established by 

 systematists from the time of Linnaeus to the present period- This 

 shell is denominated in the Linnasan Catalogue of the rarities of the 

 Museum of Ulrica, the Queen of Sweden, his patroness, Bulla 

 Achatina. We are adverse to innovation where it can be avoided, 

 but we must confess the appropriation of this shell to the Bulla genus 

 does not well accord with our ideas, although perhaps there is no 

 other in the Linnaean system to which it can with more propriety be 

 referred. With Muller this shell is a Buccinum, which in some 

 respects may be better. It is the Helix Achatina of Daubenton, 

 and to the genus Helix it has also some claim. With Bruguiere it 

 is Bulimus Achatinus, and with the Bulimus genus as laid down by 

 that author it has a near affinity, but again it differs from Bulimus 

 as characterized by others : and lastly, we find it in the arrangement 

 of Lamarck as the first species of his genus Achatina ; and under the 

 name of Achatina Perdix it is now distinguished by those who follow 



