PLATE XXI. 



LiMN^us. In and near fresh-water. 



Fig. 



1, 2. L. PEREGER, Milller {Buccinum.) — Helix, Turho, BnUmtis, and 

 L. putris, infiata, teres, lutea, limom, ovata, vulgaris, mar(jinata, 

 intermedia, lacustris, etc. — Sprins^s and ponds, Cc. 



3. L. STAG.VALis, Linn. [Helix.) — Buccinum, Tnrljo, etc., stagnalis, 



fragilis, and major, etc. — Ponds, etc., not so generally as No. 1, 

 "2,0. 



4. L. PALUSTiiis, Mailer, {Bucc.) — Helix and L. fragilis, fontinalis, 



stagnalis, etc. — Ditches, ponds, etc., C. Whorls more nume- 

 rous and less rapidly enlarged than No. •'}. 



5. L. AUKicuLARins, Linn. [Helix.) — L., Helix, Bucc, Turbo, Buli- 



mus a., paialus, etc. — Near London, Swansea, etc., Mc. Aper- 

 ture very wide, and outer lip partially reflected. 



6. L. ACUTDS, Jeffrej/s. — L. auricularius, var. B. M. — Oban, Clumber 



Lake, Bloonifield, Kent, R. Apex sharp and tapering; aperture 

 smaller than No. 5. 



7. L. iK\}scx-vvLi]?,,Miiller,[Bucc.) — if., 5., and L.truncaius,fossarius, 



minntus, Umosus, etc. — Partly amphibious, generally diffused, C. 

 Small, spire equal to body. 



8. L. GLABEK, Miiller, [Buccinum.) — H., B., and L. oetanfracta, pere- 



grina, elongata, octona, leucosf.oma, etc. — Fresh and brackish 

 marshes, Stafl'ord, Somerset, York, etc., R. Spire longer than 

 aperture. 



9. L. INVOLUTUS, Hareey. — Am.phipeplea i. — Lake near Killarney, 



Belfast, Rr. Spire almost covered. 



10. L. GLDTiNosus, Miiller, [Buccinum.) — Helix, Amphipeplea, and L. 



■ — -Windermere, etc., Mr. Oval. 



11. L. BuKNETTi, Alder. — Lakes in Dumfries and Breconshire. In- 



flated; spire flat; colour opaque-amber. 



Physa. In and near fresh- water. 



12. P. HYPNORUM, Linn. [Bulla.) — Helix, Phi/sa, Lhnnaa, and Aplexa 



turrita and marmorata. Pools and lakes, Brit, generally, C. 



13. P. FONTIN.^LIS, Linn. [Bulla.) — Turbo, Planorbis, Bulimus, and Ph. 



adversus, bulla, biMoides, and fiuciatilis. ■ — Brit, pools, lakes, 

 and ditches, C. 



Ancylds. In fresh-water. 



14. 15. A. FLiiviATiLis, Miiller. — Patella lacustris. — Running streams, 



on stones and plants generally, C. Oval, apex turned to left. 



