SYNOPSIS 



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



I. CEPHALOPODA. 



Sepiad.e, Loligo. 



SiPHONiDiE, Spirilla. 



II. PTEROPODA. 

 Clionid^, Clio. 



III. GASTEROPODA. 



a. NUDIBRANCHIA. 



DoriDjE, Doris. 



Tritonid.1:) Tritonia. 



GLAuciDiE, Eolidia, Cavolina, Filurus. 



b. INFRABRANCHIA. 

 HEMiPHYLLiDiE, Ancylus. 



c. TECTIBRANCHIA. 

 AcERIDiE, Bulla. 



d. PULMOBRANCHIA. 



LiMAciD^, Limax, Arion, Tebennophorus. 



HELioin;E, Vitrina, Helix, Pupa, Succinea, Bulimus. 



AURICUI.ID.E, Auricula. 



LimniadjE, Planorbis, Limnea, Physa. 



c. OPERCULATED PULMOBRANCHIA. 



CyclostomidjE, Cyclostoma. 



Helicinid;e, Hclicina. 



/. PECTINIBRANCHIA. 



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



TuRBiNiDiE, < Cinguia, Lacuna, Turritclla, Pyramis, Odostomia, Vermetus, 



(_ Skenea, Valvata, Natica. 



TrochiDjE, Ampullaria, Jantliina, Scalaria, Tornatella, Pirena. 



