PA LU DI N A, 



Bivtr Snail. 



Generic Character. 



Testa otata, spiralis, tenuis, umhilicata. Aper fur a semi- orbicular is, ad 

 labii antcrioris apicem subaiigulata. Operculum cortieum. 



Animal fluxiatile, branchiatum, xiviparum, rostro brerissimo ; oculis ad 

 basin externum tentaculorum acuturum 2 appositis ; pedis margiuc 

 antico duplici ; lateribus antice alis partis instructis ; aid dexterd 

 involutd in canalem per quern aqua in tracheam introducitur. 

 Typus Genericus Helix vivipara, Lin. 



Shell ovate, spiral, thin, umbilicated. Aperture nearly orbicular, 

 slightly angulated at the top of the inner lip. Operculum 

 horny. 



Animal fluviatile, branchiated , viviparous; rostrum very short; eyes 

 placed at the external base of two pointed tentacula ; anterior 

 border of the foot double ; on each side the fore part of the 

 body a small wing ; that on the right side is folded into a 

 channel, by which the water is introduced into the respiratory 

 canal. 



Generic Type Viviparous Snail Pennant. 



The common Shell above quoted, inhabiting many of our 

 rivers, will serve as an excellent example of this genus, 

 which is not numerous, and confined to fresh waters ; the 

 animals, inhabiting the European species, appear to have been 

 thoroughly investigated by the continental naturalists ; and 

 from their account of its singular construction, the above 

 description has been framed. Science should make no dis- 

 tinction of persons or countries ; but it is rather mortifying to 

 observe, that these important discoveries in the organization of 

 animals, are pursued with zeal and ability by foreign natural- 

 ists, while most of our own content themselves with expa- 

 tiating on its impossibility, and even go so far as to hint its 

 uselessness, because we can never become acquainted with 

 the animals of «// the species of shells in our cabinets : so far 

 this latter part of the argument is most true; but, to ascer- 

 tain, for instance, the animal of the Cowry, it is surely not 

 requisite we should see those of all the species (near 80 in 

 number), before we venture to describe it ? any more than it is 

 necessary completely to dissect even/ species of Locust before 

 we pronounce it to be one. Science would, indeed, receive 

 incalculable and lasting benefit, if those of our conchologists 

 who reside near the coast would pay greater attention to the 

 inhabiting animals, and less to the shells, of their neighbour- 

 hood ; for the first would supply that information they ac- 

 knowledge is so desirable, and the latter would prevent our 

 indigenous Catalogue from being crowded with many dubious, 

 and even foreign shells, 

 ri. 98. 



