NON'-MARIXE MOLJ.USCS OF ESSEX. 



59 



Clausilia — 



+ *laminata, Mont. 

 + *bidentata, Strom. 



biplicata, Mont. 



pumila, Ziegl. 

 *rolpIiii, Gray 



Cochlicopa — 



+ *lubrica, Mull. 



Azeca^ 



+ *tridens, Pult. 



elonguta, Taylor 

 Caecilianella — 



+ *acicula, Miill. 



Succinea — 



+ *putris, Linn. 

 + *elegans, Risso. 

 *oblo>iga, Drap. 

 Oncidiella — 



cdtica, Cuv. 



b Basommatophora. 



Carychium — 



+ *minimiim, Miill. 



Melampus — 



+ denticulatus, Mont. 



Alexia — • 



+ myosotis, Drap. 



Leuconia — 



+ bidcntata, Mont. 



Ancylus — 



+ yiuviatilis, Miill. 



Velletia— 



+ *laciisti'is, Linn. 



Limnaea — 



+ *auricidaria, Linn. 



+ *pereger, Miill. 



+ *palustris, Miill. 



+ *tru7icatida, Miill. 



+ *stag)ialis, Linn. 



+ glabra, Miill. 



involiita, Harv, 

 Amphipeplea — 



glutinosa, Miill, 

 Planorbis — 

 + *corneus, Linn. 

 + *albus, Miill. 

 + *glaber, Jeff. 

 + *tiaiit ileus, Linn. 

 -h *cariiiatus, Miill. 

 + *marginatus, Drap. 

 + *vortex, Linn. 

 + *spirorbis, Miill. 

 + *contortus, Linn. 

 + *fontanus, Light f. 

 + *lineatus, Walker 



Physa — 



+ *fontinalis, Linn. 

 + *hypjiorum, Linn. 



II. Pro.sobr.\nchiata. 



Paludestrina — 



+ conftisa, Frau. 

 + jenhinsi. Smith. 

 + *ventrosa, Mont. 

 + *stagnalis. Bast. 

 *marginata, Mich. 



Bythinia — 



+ *tentaculata, Linn. 

 + *leachii Shepp. 



Vivipara — 



+ *vivipara, Linn. 

 + *contecta, Millett 



Valvata — 



+ *piscinalis, Miill. 

 + *cnstafa, Miill. 



Assiminea — 



+ grayana, Leach 



Pomatias — 



+ *elegans, Miill. 



Acicula — 



*lineata, Drap. 



Neritina — 



+ *Jluviatilis, Linn. 



B. PELECYPODA. 



Dreissensia — 



+ *polymoyplia, Pall. 



Unio — 



*littoralis, Lam. 

 + *pictonim, Linn. 

 + *tumidiis, Retz. 



margaritifer, Linn. 



Anodonta — 



+ *cyg)iaca, Linn. 



Corbicula — 



*fluminalis, Mull. 



Sphaeriutn — 



+ rivicola, Leach. 

 + *corneum, Linn. 

 + ovale. Per. 

 + lacustre. Mull 



Pisidium— 



+ *amnicum, Miill. 



*astartoides, Sandb. 

 + *pusil!uin, Gmel. 

 + nitidum, Jenyns. 

 + *fontinale, Drap. 

 + milium, Held. 



