CHAPTER LXX: THE CHRYSALIS SHELLS 

 AND DOOR SHELLS 



Family PupiLLiOiE (Pupid.^). 



Shell cylindrical, many-whorled, usually minute, with con- 

 tracted aperture, guarded by teeth, often set with internal lamel- 

 lae; apex blunt; radula as in Helix. 



A family of minute mollusks. 



Megaspira elatior, Spix., a forest snail of Brazil, is excep- 

 tional. It bears an auger-shaped shell, 2^ inches long, of about 

 twenty-five coils. 



Genus PUPILLA, Leach (PUPA, Lam.) 



Characters of the family. A large genus of universal distri- 

 bution. The well-established name, Pupa, of Lamarck is obliged 

 to give place to the earlier one, given by Leach. 



The Armed Chrysalis Shell (P. armifera, Say) is almost 

 thimble-shaped; inside the thick, recurved lip the aperture is 

 guarded by numerous teeth and folded plaits. Animal black. 

 Length, J inch. 



Habitat. — Damp soil about grass plots, or under logs. East- 

 ern half of United States. A few other species are found in this 

 country. 



Genus VERTIGO, Mull. 



Shell minute, ovate, with blunt apex; aperture with four 

 to seven folds; lip expanded, white. Animal as in Pupa, but 

 lacking one pair of tentacles. Distribution world-wide. One 

 hundred species. 



V. ovata, Say, dark amber-coloured, stout, with semi- 

 circular, toothed aperture, and only J inch long, is scarcely 



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