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tat and functions of the animal, and the form and cha- 

 racter of the shell, that the naturalist in vain look- 

 ed for those concurring testimonies, and distinguish- 

 ing generic characters, by which alone he could 

 satisfy his mind on the propriety of adopting them 

 as his guide in classing the object under his ex- 

 amination, and determining its genus. The G. He- 

 lix, as it now stands established by Lamarck, com- 

 prehends such of the shells, so called by Linnaeus, 

 as present constant and similar generic characters 

 in all their species, viz. their being orbicular, con- 

 vex, or conoid, generally globular; aperture entire, 

 of a greater width than length, very oblique, con- 

 tiguous to the axis of the shell, having the margin of 

 it disunited by the angle of the previous evolution or 

 whorl; the right margin or lip thickened or reflect- 

 ed inwards, a circumstance which never takes place 

 in marine or fresh water shells, whose general appear- 

 ance might, in other respects, resemble that of the He- 

 lix. The substance of the shell is never pearly, though 

 externally and internally highly polished: the animals 

 conceal themselves, during the heat of the day, in damp 

 shady places, and during winter, in the holes of trees 

 and walls, or beneath the surface of the ground, some of 

 Ihem closing the aperture of their shell with a false cal- 





