SYNOPSIS 



OF THE 



NORTH AMERICAN FAMILIES AND GENERA OF MOLLUSCA DESCRIBED IN THIS WORK. 



I. CEPHALOPODA. 



Sepiad*, Loligo. 



Siphonidjs, Spirula. 



II. PTEROPODA. 



CLIONID.E, Clio. 



III. GASTEROPODA. 



a. NUDIBRANCHIA. 



Dorid.e, Doris. 



Tritonidj;, Tritonia. 



Glaucid2e, Eolidia, Cavolina, Filurus. 



b. INFRABRANCHIA. 

 Hemiphyllidje, Ancylus. 



c. TECTIBRANCHIA. 

 Acerid^e, Bulla. 



d. PULMOBRANCHIA. 



Limacid*, Limax, Arion, Tebennopliorus. 



Helicidje, Vitrina, Helix, Pupa, Succinea, Bulimus. 



Aurictjlid.e, Auricula. 



Limniad^;, Planorbis, Limnea, Physa. 



c. OPERCULATED PULMOBRANCHIA. 



CyclostomidjE, Cyclostoma. 



Helicinid.e, Helicina. 



/. PECTINIBRANCHIA. 



C Paludina, Amnicola, Melania, Anculotus, Io, Littorina, Margarita, 



Turbinid^e, 1 Cingula, Lacuna, Turritella, Pyramis, Odostomia, Vermetus, 



( Skenea, Valvata, Natica. 



Trochid^:, Ampullaria, Janthina, Scalaria, Tornatella, Pirena. 



