Remarks on Classifications of 



16. Stenotrema Raf. 



Type. H. spinosa Lea. 



liirsiita Say. germana Gould. 



maxillata Gould. pustula Fer. 



stenotrema Fer. leporina Gould. 



Edgariana Lea. Lecontii Lea 



spinosa Lea. is loricata Gould. 



monodon Rack. barbigera Redf. 



17. Triodopsis Raf. 



Type. H. palliata Say. 



fallax Say. 

 tridentata Say. 

 palliata Say. 



var. obstricta Say, 

 appressa Say. 

 divesta Gould, 

 elevata Say. 



Rugeli Shuttl. 

 iuflexa Say 



is inflecta Say. 

 loricata Gould, 

 clausa Say. 

 vultuosa Gould, 

 hopetonersis Shuttl 



18. Mesodon Raf. 



Type. H. albolabris Say. 



thyreoides Say. 

 bucculenta Gould, 

 exoleta Binn. 



var. albolabris Say. 

 major Binn. 



is var. of albolabris Say, 

 profunda Say. 

 Sayi Binn. 



dentifera Binn. 



var. Roemeri Pfr. 

 raultilineata Say. 

 pennsylvanica Green. 

 Jugallsiana Shuttl. 



is Ingallsiana Shuttl. 

 Mitchelliana Lea. 



Larpa Say. 



pulchella Mtlll. 

 a. costata. 

 h. pulchella. 



20. AcANTHiNULA Beck. 

 Type. H. aculeata Miill. 



21. Vallonia Risso. 



23. Fruticicola Held. 



Type. H. hispida L. 

 rufescens Penn. hispida L. 



