163 



EXPLANATION OF THE PLATES. 



Fig. 



37. The two valves of Area Pectim- 



culus. 

 a. a. the beaks. 



38. Area NocE. 



Plate 4. 



39. One valve of Ostrea Malleus. 



a. the hollow where the carti- 



lage is fixed. 



b. the hollow for the byssus. 



c. the muscular impression. 



40. Ostrea Ephippiiim. 



41. opercularis . 



a. the connecting cartilage. 

 b.b. the ears. 

 "43. Ostrea Lima. 



44. Crenatula Mt/tiloides. 



45. Anomia Grj/phus. 

 46. Plueenta. 



a. the two diverging ridges. 



b. the corresponding hollows. 



47. The flat valves of Anomia Epkip- 



pium. 

 a. the perforation. 



48. Mytilus Modiolus. 



49. anatinus. 



60. Hirundo. 



31. Pinna muricata. 



Plate 5. 

 33. Argonaiita Argo. 



54. Nautilus Pompilius. 



a. a part of the outer shell re- 

 moved, to show the inter- 

 nal construction. 



55. Nautilus Spirula, 



66. obliqmts magnified. 



a. the natural size. 

 37. Nautilus /V/sc/w magnified. 



a. the natural size. 



58. Nautilus Becearii. 



59. Conus marmoreus, with the ani- 



mal. 



Fig. 



59. r/.ff. the horns. 

 b. b. the eyes. 



c. the windpipe or breathing- 



tube. 



d. the operculum. 



60. Conus Mercator. 



a. the spire. 



b. the base. 



e. the outer lip. 

 e. the apex. 



QX.a.Cj/prxa Caput serpentis, with the 

 animal. 

 b.b. the horns. 



c. the windpipe. 



d.d. the side membranes which 

 cover the shell. 

 Ql.b.Cj/proia Caput serpentis. 

 61. c. A young shell of the Cyprma; 

 genus not perfectly formed. 



62. Bulla aperta. 



63. TerebeUum. 



64. Ficus. 



65. Ampulla. 



66. virginea. 



67. cylindrica. 



Plate 6. 



68. Volula porphyria. 

 69. Oliva. 



70. musica. 



a. the folds or teeth on th 



pillar lip. 



b. the hollow or notch at the 



base. 



c. the outer or right lip. 



d. the apex or point of the 



spire. 

 71. Valuta papalis. 



72. mereatoria. 



73. glabella. 



74. cancellata? 



73. Pyrum. 



a. the teeth on the pillar lip. 

 76. Valuta Cojfea. 



