"It was the same with me at first," declared Marama, smiling, "but if you look closely in the rough places, on piles of coral and along the edges of the gullies, you will see the oysters there by hundreds. It is easy to mistake them for lumps of rock--coral and barnacles grow on them as on the rock itself. They lie open like the _pahua_ (the tridacna clam), but that helps you little, for their fringes are not blue and yellow like the clam's tongue." I did not waste my strength by climbing into the canoe, but lay in the water resting as I had seen the natives do. When five minutes had passed I put down my glasses and went to the bottom again, and this time I saw two pearl-oysters. I found them at the edge of the gulley, when I was on the point of giving up in despair of seeing the elusive things. They looked for all the world like irregular lumps of coral, projecting like hundreds of other lumps from the rocky wall, and I would have passed without a second glance if one of them had not moved. Though they have no eyes, in our sense of the word, all bivalves which do not habitually lie buried in sand or mud seem to possess a subtle sense of light. As my body passed over the oyster, shutting off the light, the creature was thus mysteriously warned, and instantly its shells closed with a smooth swiftness. Looking more closely, I recognized the outlines of the _margaritifera_, the pearl oyster, beneath a protective growth of parasites, and grasping it with my gloved hand, I endeavored to wrench it from its fibrous moorings. As I struggled to free it from the coral, the water must have been agitated, for another rough lump closed with the same smooth swift movement, revealing a second great oyster. By this time I had been under nearly a minute, and though I tugged with all my might I was unable to wrench the shell free before I rose. "I have seen the oysters," I told Marama, as I lay resting in the sunlight, "but try as I would, I could not tear one loose!" He picked up an opened shell from the bottom of the canoe. "Take hold thus," he instructed me, "and turn the oyster with a sudden wrench. It is useless to pull. Ah--your left hand is bleeding--take care to use the gloved hand only, for the coral cuts like a knife, and oftentimes the wounds are poisoned." By the third time down I had gained confidence and was beginning to feel at home on the bottom. Now I remembered the trick of which the Paumotan diver had told me, and when I had been half a minute under water I began to let the air out of my lungs. The native had spoken truly; each little string of bubbles brought its moment of relief and enabled me to go about my work more calmly.