DHE “POLVPTE RS. 105 
Inhabiting the watery world in vast colonies, they absorb the 
limy salts of the ocean, of which they build their cells, producing 
frequently colossal structures. Their germs fall around them and 
give birth to myriads of new workers, who over-build their parents, 
and thus entomb their ancestry, piling up cells above cells in one 
vast calcareous structure of rocks which attain gigantic sizes; some 
of the reefs which fringe the Australian coast being nearly 1,000 
miles long! It is true vast ages are required to complete this 
work, but Nature is never at a loss for time to complete her works. 
A CORAL ISLAND. 
The South Sea Archipelago almost owes its existence to the 
never-ceasing exertions of these minute polypes. For untold ages 
they have worked incessantly, and have raised great and lasting 
monuments to assert the power of combination. 
The builders of these immense structures are animalcules which 
are gelatinous, fragile, small—nay, microscopical, but their number 
is illimitable; they live in myriads, and by the accumulation of 
their skeletons can produce a mass of masonry, of which the whole 
human family, working for 100,000 years, would only construct a 
very small part. When once the builders reach the surface of the 
water they cease to increase, for they are children of the sea. They 
