xiv LIST OF ILLUSTRATIONS 



FIG. PAGE 



23. Formation of an Atoll, according to Ainsworth . . 95 



24. Formation of an Atoll, according to Murray . . . S6 



25. Diagram illustrating the Difference between the Theories of 



Darwin and Murray ..... 98 



26. The Site of the First Boring, Funafuti .... 103 



27. Lagoon Beach, Funafuti ..... 104 



28. Forest Scene, Funafuti ...... 105 



29. The Mangrove Swamp, Funafuti .... 107 



30. A Raised Pinnacle of Coral, Funafuti . . . .109 



31. Funafuti, on the Ocean Side ..... 110 



32. Funafuti, Tidal Platform and Margin of Reef . . .111 



33. A Group of Natives, Funafuti ..... 115 



34. Submarine Profile of Funafuti ..... 117 



35. Section in a Chalk Quarry ..... 135 



36. View of a Chalk Pit at Horstead ..... 137 



37. Coccoliths, after H. Lohmann ..... 139 



38. Examples of Flints Broken Open to Show the Structure . . 141 



39. Yenus's Flower Basket (Euplectelld) .... 144 



40. A Fragment of the Skeletal Network of an Hexactinellid Sponge 



(Scleroplegma cornea, O.S.) .... 145 



41. Sponge Spicules associated with Flints .... 147 



42. Skeletal Remains of Sponges, converted into Fibrous Crystalline 



Silica 149 



43. A Silicified Foraminifera . . . . . .151 



44. Banding Produced by the Spread of Oil in Writing Paper . 153 



45. Diagram to Illustrate Volume of a Sponge and its Contents in 



Silica ........ 156 



46. A Fossil Sea-Urchin (Anancliytcs) from the Chalk . . 158 



47. Siliceous Shell of a Common Diatom (Pinnularia) . . 161 



48. A Polyzoon (Plumatella) . . . . .168 



49. Hydra vulgaris . . . . . . .169 



50. Diagram to Illustrate the Seasonal Changes in the Freshwater 



Planctone ....... 174 



51. A Freshwater Crab, represented on a Sicilian Coin . . 175 



52. Larval Form (glochidium) of the Freshwater Pond Mussel . 179 



