"A starfish!" murmured Tom. This accounted for it, and, as he looked at the monster from closer quarters, he saw that Norton had spoken the truth.
Small starfish, or even large ones, two feet or more in diameter, may be seen at the seashore almost any time. Nearly always the specimens cast up on the beach are in extended form, either limp, or dead and dried. In almost every instance they are spread out just as their name indicates, in the conventional form of a star.
But a starfish alive, and at its business of eating oysters or other shell animals in the sea, is not at all this shape. Instead, it assumes the form of a sack, spreading its five radiating arms around the object of its meal. It then proceeds to suck the oyster out of its shell, and so powerful a suction organ has the starfish that he can pull an oyster through its shell, by forcing the bivalve to open.
And it was a gigantic starfish, a hundred times as large as any Tom had ever seen, that had Ned in its grip. The creature had doubtless taken the diver for a new kind of oyster, and was trying to open it. An octopus has suckers on the inner sides of its eight arms. A starfish has little feelers, or "fingers," arranged parallel rows on the inner side of its arms—thousands of little feelers, and these exert a sort of sucking action.
The gigantic starfish had attacked Ned from above, settling down on him so that the head of the diver was at the middle of the creature's body, the five arms, dropping over Ned in a sort of living canopy. And the arms held tightly.
"Come on, Koku, and you, too, Norton!" called Tom through his headpiece telephone. "We'll all attack it at once. I'll fire, and then you begin to hack it. The electric charge ought to stun it, if it doesn't kill the beast!"
Tom's new electric gun, unlike one kind he had first invented, did not fire an electrically charged bullet. Instead it sent a powerful charge of electricity, like a flash of lightning, in a straight line toward the object aimed at. And the current was powerful enough to kill an elephant.
Bracing his feet on the white sand, which gleamed and sparkled in the glare of the searchlight, Tom aimed at the gigantic starfish which had enveloped Ned. Standing on either side of him, ready to rush in and attack with axe and lance, were Koku and Norton.
For an instant Tom hesitated. He was wondering whether the powerful electric charge might not penetrate the body of the starfish and kill his chum.
"But the rubber suit ought to insulate and protect him," mused the young inventor. "Here goes!"