Order STYLOMMATOPHORA 



Terrestrial; usually with two pairs of tentacles, the larger pair in- 

 vertible and with eyes at the ends, sometimes with the small an- 

 terior pair absent 

 Family HELICIDAE 



Introduced European species; medium to large; shell with a 

 fairly low spire, five to seven whorls; aperture with reflected lip; 

 foot not grooved 



Common genera — Helix Cepaea 



Family JACOSTIDAE (HELICELLIDAE) 



Introduced European species; small; shell Vv'ith lo\\i spire and 

 thin or partly reflected lip; foot not grooved (Not included in 

 the key) 



Common genera — Jacosta Monacha 



Hygromia Cochlicella 



Family HELMINTHOGLYPTIDAE 



Moderate to large; shell globose to depressed, usually banded; 

 lip thin or reflected; foot not grooved; southern and western 

 species 



Common genera — Cepolis Micrarionta 



Monadenia Sonorella 



Helminthoglypta Sonordix 



Humholdtiana 

 Family CAMAENIDAE 



Moderate si:;ed; shell pyramidal to discoidal; umbilicate; lip 

 usually not reflected or expanded; body whorl plain colored or 

 with two color bands; foot not grooved; southwestern states 

 Common genera — Oreohelix Avimomtdla 



Polygyrella Glyptostoma 



Megomphix 

 Family POLYGYRIDAE 



Small to large; shell globose to discoidal; usually plain colored, 

 sometimes banded; aperture with reflected lip, often toothed; 

 foot not grooved 



Common genera — Polygyra Triodopsis 



Stenotrema AMogona 



Praticolella V^espericola 



Mesodon Ashmunella 



Trilohopsis 

 Family SAGDIDAE 



Small; shell conic to discoidal; plain colored; lip thin; foot not 

 grooved 



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