SYSTEMATIC INDEX. 



37. Physa fontinalis. Stream Bubble-shell, 



14. Planorbis. Coil-Shell, .... 



38. Planorbis Vortex. Angular-mouthed Flat Coil-shell, 



A. P. Vortex crassulus. Thickish, 



B. P. Vortex spirorbis. Bound-edged, 



39. Planorbis contortus. Contorted Coil-shell, 



40. Planorbis albus. Bristly Coil-shell, 



41. Planorbis imbricatus. Crested Coil-shell, 



15. Ancylus. Lid-Shell, .... 



42. Ancylus nuviatilis. Oval Lid-shell, 



ORDER II. GASTEROPODA PECTINIBRANCHIAT A 



16 



1? 



18, Natica. 

 45. 

 46. 

 47. 

 48. 

 49. 

 50. 



51, 



SECTION I. ASIPHONATA, 

 FAMILY I. PALUDININA, 

 Paludina. Marsh-Shell, 



43. Paludina vivipara. Viviparous Marsh-shell, 

 Btthinia. Bythinia, 



44. Bythinia tentaculata. Tentaculated Bythinia, 

 FAMILY II. NATICINA. 



Natica, .... 

 Natica monilifera. Beaded Natica, 

 Natica rutila. Buddy Natica, 

 Natica Alderi. Alder's Natica, 

 Natica nitida. "White Natica, 

 Natica helicoides. Helicine Natica, 

 Natica stmalida. Dull-coloured Natica, 



19. Neritina. Neritine, 



51 . Neritina nuviatilis. Biver Neritine, 



FAMILY III. TURBININA, 



20. Trochus. Pyramid-Shell, 



52. Trochus zizyphinus. Zizyphine Pyramid-shell, 



53. Trochus con'uloides. Conuloid Pyramid-shell, 



54. Trochus millegranus. Granulated Pyramid-shell, ) 

 Trochus Martini. Martin's Pyramid-shell, } 



55. Trochus umbilicatus. Umbilicated Pyramid-shell, 



56. Trochus cinerarius. Grey Purple-streaked Pyramid-shell, 



57. Trochus tumidus. Tumid Pyramid-shell, 



21. MONODONTA. MONODONTA, 



58. Monodonta crassa. Solid Monodonta, 



22. Phorcus. Phorcus, 



59. Phorcus Margarita. Pearly Phorcus, 



23. Skenea. Skenea, 



60. Skenea depressa. Brown Skenea, 



61. Skenea serpuloides. Serpuline Skenea, 



62. Skenea divisa. Semistriated Skenea, . 



24. Littorina. Periwinkle, . 



63. Littorina littorea. Common Periwinkle, 



64. Littorina jugosa. Bidged Periwinkle, . 



65. Littorina rudis. Coarse Periwinkle, 



66. Littorina saxatilis. Bock Periwinkle, . 



67. Littorina tenebrosa. Marsh Periwinkle, 



53, 



Pages 

 49, 112 

 49,113 



49, 114 

 50,116 

 50, 117 

 50,118 



50. 119 



50. 120 



50. 120 



50. 121 



50. 121 



50, 122 



51. 122 



51, 122 



51,123 



51, 123 



51, 124 



51, 124 



61,124 



125, 345 

 51, 126 



52. 126 



52. 127 



52. 128 



52. 128 



52. 129 



52. 129 



52. 130 



52. 131 



53. 131 



53. 132 



1C2, 340 



53, 132 



53. 133 



53. 133 



325 

 325 



53. 134 

 53,134 

 53,134 



54,134 



54. 135 



54, 135 



54,135 



54. 136 

 326 



54. 137 

 54, 138 

 54,138 



