116 



siphons separated to their base. They inhabit rivers and estuaries in the 

 tropical countries of both hemispheres, but are most abundant in the penin- 

 sulas and islands of the eastern seas, where they live imbedded in the mud 

 of mangrove-swamps. In Europe the genus is represented by Cyclas. 



1. sequilateralis, Desk. 



2. affinis, id. 



3. Africana, Krauss. 



4. ambigua, Desk. 



5. angulata, id. 



6. anomaln, id. 



7. arctata, id. 



8. atrata, id. 



9. australis, id. 



10. Bengalensis, id. 



11. Bensoni, id. 



1 2. Brasiliana, id. 



13. Buschii, Phil. 

 11. Caroliniana, Base. 



15. Cashmiriensis, Desk. 



16. Ceylamca, Cliem. 



17. Charpentieriana, B. 



18. Childrenae, Gray. 



19. compressa, Mouss. 



20. coinpta, Desk. 



21. consobrina, Caill. 



22. corbuloides, Desk 



23. convexa, id. 



24. cor, Lamarck. 



25. cordiforrnis, Reel. 



26. Cumingii, Desk. 



27. cuneata, Jonas. 



28. cyclostoraa, Bourg. 



29. cyprinoides, Quoy. 



30. decipiens, Ztes/i. 



31. Deshayesiana, B. 



32. divaricata, Desk. 



33. dura, ic?. 



34. eximia, Bunk. 



35. Essingtonensis, Ztes/fc. 



36. expansa, Mouss. 



37. fallax, Des7i. 



Species. 



38. Floridana, C'owr. 



39. Fontainei, D'Orb. 



40. flurninalis, Mull. 



41. flurninea, i^. 



42. fluviatilis, id. 



43. Galatliea3, Morch. 



44. Gauritziaua, Krauss. 



45. grandis, ZtesA. 



46. liumerosa, ic?. 



47. impvessa, id. 



48. incerta, ie?. 



49. incrassata, id. 



50. inflata, id. 



51. inquinata, i<?. 



52. insignis, id. 



53. Isocardioides, it?. 



54. Jayensis, Lea. 



55. Jukesii, Desk. 



56. Keraudrenia, Ze*s. 



57. Largillierti, Phil. 



58. lauta, ZV«//. 



59. lenticularis, id. 



60. limosa, Maton. 



61. Mactroides, ZtesA. 



62. maritima, Adams. 



63. megadesma, ZW<. 



64. Moquiniana, Bourg. 



65. Moussoni, Desk. 



66. Nepeanensis, Zm. 



67. nitens, Phil. 



68. nitida, ZtesA. 



69. nitidula, id. 



70. notabilis, id. 



71. obesa, Hinds. 



72. oblonga, Qwoy. 



73. obscura, Dm//. 



74. obsoleta, *V. 



75. occidens, Bens. 



76. orientalis, Zaw. 



77. ovalina, DesJi. 



78. pallida, w?. 



79. Panormitana, Bio. 



80. Papua, Less. 



81. Paranensis, J)' Orb. 



82. placens, 2Ta«^. 



83. placida, ZW*. 



84. producta, id. 



85. pulchella, Mouss. 



86. pullata, PAfl. 



87. pusilla, id. 



88. radiata, iTa«^. 



89. radiata, Phil. 



90. Raymondi, B. 



91. recurvata, Z?y^. 



92. rivalis, Busch. 



93. rotundata, Ze«. 



94. salmacida, -2£b/\ 



95. semisulcata, Desk. 



96. similis, e'c?. 



97. similis, Gray. 



98. sinuosa, Ztes/j. 



99. solida, Phil. 



100. sordida, Hanley. 



101. squalida, ZtesA. 



102. striatella, id. 



103. sublobata, z'<f. 



104. suborbicularis, Phil. 



105. subquadrata, Desh. 



106. sulcatina, io?. 



107. Surnatrensis, Sow. 



108. tenebrosa, Hinds. 



109. triangula, ZV«7. 



110. triangularis, Desk. 



111. triangularis, Jie/c. 



