UNIVALVES HELIX. 161 



HELIX.— , Snail or Spiral. 



DESCRIPTION OF PLATE XXIX. 



Div. I. — Fam. 3. Fig. 3. H. gualteriana. 



Dir. IV Fam.l. Fipj. 1. H. dextra. Div. VI — Fig. 5. H. glauca. 



DiT. v.— Fig. 2. H. amarula. Div. VII. — Fig. 4. H. scarabasus. 



Dir. XII.— Fam. 1. Fig. 6. H. decollata. 



Shell univalve, spiral, suhdiaphanous, brittle; aperture contracted, 

 semilunar, or roundish. 



THE numerous species which compose this extensive 

 genus are principally land or fresh water shells, a very 

 few only being- the produce of the ocean. They are 

 generally of a delicate and brittle structure, and some- 

 times transparent. 



Among the carinated Helice?, which constitute the 

 first division, may be particularised the H. lapicida, H. 

 marginata, and H. cicatricosa. The more compressed 

 or flattened species are usually called ^Yntique Lamps; 

 the H. lampas, H. carocolla, and H. lucerna are illus- 

 trative specimens. 



The H. cornea and H. vortex are characteristic of the 

 two families of the depressed species of the second di- 

 vision. 



The third division is distinguished by the sub-lunate 

 form of the aperture, and contains some of the most 

 rare and beautiful species of the genus. Of these the 

 H. sultana and H. heemastoma are most celebrated, the 

 latter, in particular, for its elegant bandings and rose- 

 colored lip. The H. pomatia is an inhabitant of the 

 M 



