92 



UNIVALVES HELIX. 



*Albus. 



Variegtitus. 



Unfjnlinus. 



Crystalliniis. 



A 1 bill us. 



Annulatus. 



*Bideus. 



* Per versus, 



Fusulus, 



Fusus, 



Sulcatus, 



Quadridens. 



Tridens. 

 *Muscorum. 



*Trifasciatus. 



* Membranaceus. 



*Interruptus. 



*Subrufus. 



*Strigatus. 



*Albidus. 



*CarinatuIus. 



*Clathratulus. 



*Crassus. 



*Pmictatus. 



*Sheppeianus. 



*Sandvicensis. 



Obtusus. 



Auriscalpiuui. 



Politus. 



Nautileus. 



Obsoletus. 



Quinquedentatus 



Pyramidalis. 



HELIX. — Snail or Spiral. 



Animal— a Limax: Shell univalve, spiral^ subdiapJia)ious, 

 brittle; aperture contracted, semilunar, or roundish. 



The genus Helix is the most numerous of an\ ; it con- 

 tains no less than two hundred and sixty-seven species, 

 among- Avhich, some are of great beauty and rarity. By 

 far the greater proportion of species are the produce of 

 the laud: many of the rest are the inhabitants of rivers 

 and fresh-waters, leaving but a verysmall residue natives 

 of the ocean. 



The Helices are, for the most part, shells of delicate and 

 brittle structure, and remarkable for their lightness ; their 

 general form is closely allied to that of the common gar- 

 den or hedge-snail, except in those species which are ta- 

 pering or elongated. Among the carinated Helices, or 

 those with an acute margin, may be reckoned the Helix 



