to'a aau; when above the surface of the water, to'a raa. A submerged
mass is to'a faa ruru, and the coral on which the waves break, to'a
auau. However, the native knows well that one species of coral, the
ahifa, is corrosive, irritating the skin when touched, and another,
which is poisoned by the hara plants, is termed to'a harahia.

Coral makes good lime for whitening walls, and is cut into blocks for
building. Many churches in Tahiti were built of coral blocks. The puny
fortifications erected by the French in the war with the Tahitians
decades ago were of coral stones, and are now black with age and
weather.

I headed my canoe toward the barrier reef, and tied it to a knob
of coral. Then I stepped out upon the reef itself, my tennis shoes
keeping the sharp edges from cutting my feet. It was the low tide
succeeding sunrise, and the water over the reef was a few inches
deep, so that I could see the marine life of the wall, the many kinds
of starfish, the sea-urchins, and the curious bivalves which hide
with their shell-tips just even with the floor of the lagoon, and,
keeping them barely even, wait for foolish prey.

The floor of the lagoon was most interesting; the prodigality of nature
in the countless number of low forms of life, their great variety,
their beauty, and their ugliness, and, appealing to me especially,
the humor of nature in the tricks she played with color and shape,
her score of clowns of the sea equaling her funny fellows ashore,
the macaws, the mandrills, the dachshunds, and the burros.

The sunlight on the water at that hour was like silver spangles on a
sapphire robe. I paddled near to the Marara, and watched her let go