UNIVALVES. 



cluster of bubbles composed of transparent vesi- 

 cles, which it can inflate with air at pleasure, and 

 thus buoy up its delicate bark. Every shell 

 contains about a teaspoonful of liquor of a most 

 beautiful red purple, which is easily discharged, 

 as soon as the animal is touched. It is said also 

 to shine by night with a phosphorescent light. It 

 inhabits the coasts of Europe, Asia, and Africa, 

 and is common in the Mediterranean. A few 

 specimens have been picked up on the Welsh 

 coasts, but these were probably driven there by 

 storms. 



HELIX Obscura. 

 SMALL BROWN SNAIL. 



Specific character. Shell sub-oval, rather ob- 

 tuse, opaque, with about six longitudinally 

 wrinkled whorls ; aperture roundish, lunar ; it is 

 of a brownish horn colour, and the outer lip 

 white, with a reflected margin ; length half an 

 inch, breadth one fourth, or one sixth. These 

 shells are usually covered with an epidermis, 

 which varies according to the situations they 

 occupy ; and the colour being regulated by that 

 of the substance to which the Helices attach 

 themselves, they escape observation. 



