When we reach the shores of the West Indian islands and the keys of Florida the greatest abundance and variety of living forms are found. The submerged rocks blossom with flower-like sea anemones of every colour. Corals, branching like trees and bushes on the sea floor, form groves under water. Among them brilliant-hued fishes swim, and highly ornamented shells glide, as people know who have gazed through the glass bottoms of the boats built especially to show visitors the wonderful sea gardens at Nassau, Bahama Islands, and at Santa Catalina Island, southern California. On every beach the skeletons of animals which die help to build up the land; though the process is not so rapid in the north as on the shores that approach the tropics. The coast of Florida has a rim of island reefs around it built out of coral limestone. Indeed, the peninsula was built by coral polyps. Houses in St. Augustine are built of coquina rock, which is simply a mass of broken shells held together by a lime cement. Every sea beach is packed with shells and other remnants of animals and plants that live in the shallow waters. Deeper and deeper year by year the sand buries these skeletons, and many of them are preserved for all time. Thus what is sandy beach to-day may, a few million years from now, be uncovered as a ledge of sandstone with the prints of waves distinctly shown, and fossil shells of molluscs, skeletons of fishes, and branches of seaweed--all of them different from those then growing upon the earth.