When Rachel Carson thinks of the sea floor, she thinks of sedimentation, of the layers of rock, soil, shells, and ash slowly (or quickly) drifting down and becoming part of the sea floor. And the ice burgs carry rocks down, the rives carry stones and shells, and dirt.
The millions of shells drift down, and become fossils. They are the most plentiful, for there are many little creatures with shells in the sea. It is like a Great Snowfall, with all of the shell, rocks, and the rest as flakes in this blizzard.
There is an interesting shell-creature, the Globigerina, a unicellular creature, and it makes its own shell! It divides in two, and then makes two new shells, letting the old one fall. In lime-rich, warm waters this creature multiples rapidly. This little creature adds its bit to the Great Snowfall.
More later!
Bell
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