Spawn of the Venus Sea

What was this ghastly inhabitant of Venus' Dead Sea—this multiple-life monstrosity.
With a tremendous snap, the taut steel cable humming in over the stern sheaves suddenly leaped high. The winch screamed briefly as the cable skipped its guides. Before power could be shut off it had snarled badly, and the frayed end of it had thrashed a splintery dent into the Mermaid's deck.
By this time, Second Mate Stanley Kort reflected grimly, the net itself had probably bottomed on the floor of Venus's largest ocean—the Molo Ivrum , or Deadly Sea, thus named for the paradoxical reason that it teemed with life, most of it decidedly unpleasant.
Hands clenched, Kort stared from the plaskon windows of the wheelhouse. Through the thin haze blanketing the deck he could see net tenders and seamen stolidly staring forward. The cable lay in a vicious tangle between winch house and stern. Nobody looked at it.
They were waiting for orders, as they always waited when Kort held deck command. Were Hodge up here, or even Pratt, the third mate, the net tenders would have laid hold of the snarled steel by now. With Kort it was different.
Or was it he who was different, he who hadn't been trained in the hard school of this sort of seamanship? A man who'd won his papers in passenger service wasn't wanted aboard a floating cannery. Kort wished he had known a month ago how it would be. He should have left Venus after being discharged from the Corinthia , instead of trying to start anew in the cannery service.
His clenched fist opened.
Break out a magnetic! The deck speakers amplified his voice to stentorian volume, galvanized the crew into sullen action. Men untangled the steel, spliced a new length to it, and swung the magnetic grapple over the side.
With the grapple magnets drawing two hundred amps, the ship swung in a clumsy circle. Half an hour passed, marked only by the screech of cannery boilers popping off every five minutes. From forward came the stench of cleaning platforms, the clop-plop of trimming machinery.