80 



INDEX. 



Fig. Page. 



25 Helix umbilicata 42 



26 Helix limbata 43 



27 Clausilia laminata 52 



28 Clausilia biplicata 53 



29 Clausilia plicatu la 53 



30 Clausilia nigricans 54 



31 Clausilia nigricans var 



dubia 54 



32 Zua lubrica 54 



33 Azeca tridens 55 



34 Helix pygmsea 43 



Plate VII. 



1 Bulimus acutus 43 



2 Bulimus Lackhaniensis 44 



3 Bulimus obscurus 44 



4 Pupa umbilicata 45 



5 Pupa muscorum 46 



6 Pupa Anglica 46 



7 Pupa secale 47 



8 Pupa edentula 47 



9 Pupa minutissima 48 



10 Pupa pygmsea 48 



11 Pupa substriata 49 



1 2 Pupa antivertigo 49 



13 Pupa pusilla 50 



14 Pupa Venetzii 50 



15 Balsea fragilis 51 



16 Achatina acicula 56 



17 Planorbis corneus 59 



18 Succinea putris 57 



1 9 fSuccinea oblonga 58 



20 Physa fontinalis 58 



21 Planorbis glaber 61 



22 Planorbis nitidus 64 



23 Planorbis nautileus 61 



24 Planorbis carinatus 61 



25 Planorbis lacustris 64 



Fig. 



26 Physa hypnorum 59 



27 Planorbis albus 60 



28 Planorbis marginatus... 62 



29 Planorbis spirorbis 63 



30 Planorbis vortex 63 



31 Planorbis contortus 63 



32 LimnsBus glutinosus ... 69 

 3 3 Limnseus involutu s 69 



34 Limnaaus stagnalis 67 



35 Limnaeus truncatulus... 68 

 3 6 Limnseus glaber 68 



37 Ancylus fluviatilis 70 



38 Ancylus obi on gus 70 



39 Limnseus palustris 69 



40 Limnseus Burnetti 66 



41 Limnseus pereger 65 



42 Conovulus denticulatus. 72 



43 Conovulus bidentatus ... 71 



44 Conovulus bidentatus 



var albus 71 



45 Limnseus auricularius... 66 



46 Carychium minimun ... 72 



47 Acme lineata 74 



48 Cyclostoma elegans ... 73 



Plate VIII. 



1 Neretina fluviatilis 16 



2 Assiminia Gray ana ... 19 



3 Paludina Listen 17 



4 Planorbis albus 60 



5 Succinea putris 57 



6 Helix Cantiana 32 



7 Conovulus denticulatus. 72 



8 Cyclas cornea 8 



9 Cyclostoma elegans ... 73 



10 Limnseus auricularius . . 67 



11 Anodonta cygnea ...14,15 



