169 



muzzle, at the base of which are two slender tentacles, with the 

 eyes sometimes sessile, sometimes on short pedicles. 

 Shell ; ovate or conoidal, covered ivith a sombre-olive epidermis ; 

 spire somewhat turreted, often eroded ; whorls round, smooth or 

 heeled ; aperture round or ovate, the margin being mostly con- 

 tinuous, and the lip simple. 



The Paludinm are smaller and more numerous than the Ampullarice, 

 and more decidedly aquatic. There are few fresh-water streams in any 

 part of the world without them, and in the great river countries of India 

 and America they are especially abundant. The shells are of a similar 

 dull-greenish hue, and the soft parts, presenting the same contrast of 

 colour and pattern as in the preceding genus, are variously spotted on a 

 coppery or golden ground, while a few are dark blue-black, encircled by a 

 white line. 



Some of the Paludina are viviparous, and some are oviparous, and the 

 shells of the young fry are covered more or less with bands of hairs. A 

 small oviparous species, inhabiting our own ditches and canals, was made 

 a genus by Dr. Leach, with the name of Bythinia, and an interesting 

 group dwelling in the brooks and rivers of South America, having their 

 eyes sessile and operculum formed in a spiral, have been arranged in a 

 separate genus by D'Orbigny, under the title of Palndestrina. 



1. abbreviata, Michaud. 19. 



2. achatina, Lamarck. 20. 



3. acuta, Deshayes. 21. 



4. altalis, Raveual. 22. 



5. anatinum, Desh. 23. 



6. andecola, D'Orbigny. 24. 



7. angularis, Midler. 25. 



8. angulata, Lea. 26. 



9. atra, Villa. 27. 



10. australis, D'Orbigny. 28. 



11. Bengalensis, Bowdich. 29. 



12. bicarinata, Desm. 30. 



13. bicolor, Sowb. 31. 



14. Boissieri, Charpen. 32. 



15. brevis, Michaud. 33. 



16. Bulimoidea, id. 34. 



17. Bulimoides, Lamarck. 35. 



18. charrana, D'Orbigny. 36. 



Species. 



contorta, Shuttleworth. 3 7 . 



Coosaensis, Lea. 38. 



costata, Quoy. 39. 



crassa, Nuttall. 40. 



Cumingii, D'Orbigny. 41. 



culminea, id. 42. 



Cyclostomatiformis. 43. 



cylindrica, Parreys. 44. 



decisa, Say. 45. 



decollata, Sewasc/t. 46. 



diaphana, Michaud. 47. 



dissirailis, Say. 48. 



doliaris, Gould. 49. 



erosa, Ziegler. 50. 



Ferussacina, Desm. 51. 



fontinalis, Philippi. 52. 



fusca, D'Orbigny. 53. 



genicula, Conrad. 54. 



Georgiana, Lea. 

 gibba, Michaud. 

 gigantea, Busch. 

 gigas, Lesson. 

 grana, Say. 

 granum, Menke. 

 Haleiana, Lea. 

 Hamiltoni, Metcalfe. 

 imperialis, Lea. 

 impura, Lamarck. 

 incrassata, Lea. 

 inflata, Benson. 

 Integra, Say. 

 intertexta, id. 

 Isabelliana, D'Orb. 

 Javanica, Busch. 

 lacustris. Beck. 

 lapidum, D'Orbigny. 

 z 



