CHAPTER XLVII: THE HELICINAS 

 Family HELiciOiE 



Shell top-shaped, globose or depressed; aperture semi- 

 lunar; columella callous; lip thick; operculum not spiral, made 

 of overlapping plates. Head bearing a stout, blunt proboscis; 

 foot long; radula long, narrow; jaw absent. A tropical family 

 of several genera, living in damp situations in forests. 



Genus HELICINA, Lam. 



Characters of the family. Three hundred and fifty species. 

 Distribution, world-wide. 



H. orbiculata, Say, is a tiny globular shell, brownish yellow, 

 sometimes spotted, with a thick white lip. The operculum folds 

 back upon the columella as if hinged to it \vhen the animal is 

 gliding along. Diameter, J inch. 



Habitat. — Tennessee to Texas and Florida. 



H. agglutinans, Sby., has a depressed shell and a single 

 keel, decorated with frond-like processes. The inner lip is much 

 thickened. Diameter, f inch. 



Habitat. — Philippines. 



H. Briarea, Poey., has a flattened dome almost covered with 

 brown, but white below and at the sutures. The wide aperture 

 is white and polished. Diameter, I inch. 



Habitat. — Cuba. 



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