Page:Popular Science Monthly Volume 82.djvu/539

Rh seems made of grains of gold and silver, shimmering in the penetrating sunlight. Upon the face of a precipice, large specimens of the green and corrugated abalones rest. The shell of each is covered with a luxuriant growth of algae, hydroids and tentacled tube-worms, which mask the creature from its enemies. All about are large fish which swim close and peer through the glass window of the helmet. An enormous sting-ray indifferently floats by. One has a fellow feeling with these unfrighted denizens of the deep in the fascination of observing their behavior under natural conditions.

In gathering abalones sometimes a crew is composed of six divers who work without suits up to a depth of twenty feet and some of them remain under water for as long as two minutes. These expert swimmers protect their eyes with glasses and wear cotton in their ears. They pry off the abalones with a shucking-chisel, often filling their arms on the way to the boat. Every two hours they return to the launch to be warmed at the fire. It takes the united efforts of these six men to equal the catch of one diver in a suit.

The abalone has a well-developed head and a powerful, adhesive, creeping foot. The shell is flattened, and the spire, which is such a prominent conical structure in most snail shells, is depressed and inconspicuous in this form. The last greatly enlarged whorl contains the body, especially characterized by the enormous columellar muscle, whose fibers run from their origin upon the muscle scar, or center of the shell, into the foot. Numerous contractile tentacles arise from the fringed epipodial fold, or ruff, around the base of the foot. The gills, alimentary system, reproductive glands, kidneys, heart and blood vessels and the pallial and visceral sections of the nervous system lie to the left of