Common genera — Binneya Arion 



HernphiUia Prophysaon 



Ariolimax Anadenulus 



Hesperarion Zacoleus 



Order SYSTELLOMMATOPHORA 



Slug'like; with two pairs of tentacles, the larger pair contractile 

 and with eyes at the ends 

 Family VERONICELLIDAE 



Slugs; mantle covering entire back; respiratory pore below mar' 

 gin of mantle 



Common genus — Veronicella 

 Subclass PROSOBRANCHIATA 



Shell opcrculate; with or without gills; usually with one pair of 

 nou'contractile tentacles, with a pair of stalked or unstalked eyes 

 at their bases; sexes separate 

 Order ARCHAEOGASTROPODA 



Terrestrial; no gill, mantle cavity serving as lung; operculum with 

 concentric half 'rings 

 Family HELICINIDAE 

 Shell hcliciform 



Common genera — Heliciyia Hendersonid 



Lucidella 

 Order MESOGASTROPODA 



Terrestrial; with or v^ithout a small gill; operculum with subspiral 

 markings 

 Family TRUNCATELLIDAE 



With a small gill; spire almost cylindrical; lip continuously 

 reflected 



Common genus — Trimcatella 

 Family POMATIASIDAE (CYCLOSTOMIDAE) 



No gill; shell higher than Vw'ide; lip slightly reflected 

 Common genus — Chondropoma 

 Order SCUTIBRANCHIATA 



Aquatic; gill bearing filaments on both sides 

 Family NERITIDAE 



Shell globose, with very short spire; columella area much ex' 

 panded; eyes on stalks on the outside of the bases of the 

 tentacles 



Common genera — Tsleritina Lepyrium 



Order PECTINIBRANCHIATA 



Aquatic; gill usually bearing filaments on one side 



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