PLATE XLIX. 



find Hahitat--Jluviatilis, We may also add that Seba was no kss 

 in error, if he really meant the same shell, for he calls it " Cornet de 

 Mer " from which we must conclude he regarded it as an inhabitant 

 of the marine element. 



Among the various generical changes which the science of 

 Conchology has undergone of late years those shells have not wholly 

 escaped transposition ; they appertain distinctly to the turrited family 

 of Hehces in the Linnsean mode of classification ; the generical ap- 

 pellation of Escargot, assigned to it by some writers, may be deemed 

 synonymous. Chersina, another of its generic epithets, is rather more 

 remote. Scopoli, and after him Bruguiere, proposes to name it 

 generically BuUmus, and Lamarck, De Montfort, and Cuvier follow 

 them, but each with some peculiar modification. The generical 

 distinction of the Helix genus, as defined by Linnaeus, consists most 

 essentially, besides its being a spiral shell, in the form of the mouth 

 or aperture, which is either contracted, semilunar, or roundish, a 

 character confessedly too diffuse, and well deserving of amendment. 

 The character of Bulimus consists in the shell being ovate-oblong or 

 turrited, but never orbicular, like the Helices, the aperture entire 

 and longer than broad ; the margin very unequal and disunited 

 above ; pillar lip straight, smooth, entire at the base, and not effuse. 

 In addition to this character of BuUmus, as expressed by Lamarck, 

 De Montfort proposes that the spire should terminate obtusely, 

 which is not the case with all the shells referred by other writers to 

 the Buhmus genus : he also mentions the pillar lip being smooth and 

 having an inflexion in the middle, which does not accord with the 

 definition of the genus as laid down by others. It may be also 

 added, that the Bulimes of Bruguiere have been again subdivided by 



