Chemistry comes to lobster guards' aid.

Harvesting egg-bearing lobsters is illegal, so for years some lobstermen have removed the eggs before inspectors examine their catch. The latest technique in this subterfuge involves dipping the lobsters in chlorine, which dissolves the unusually hard-to-remove glue that holds eggs to the mother's shell. In response, inspectors have recently begun to use a new test that can detect chlorine on lobsters up to 10 days after a chemical dip. They put the lobsters' swimmerets, the small appendages on their abdomens, in a solution of potassium iodide, which turns yellow in the presence of chlorine, explains Robert A. Bullis of the Woods Hole (Mass.) Marine Biological Laboratory, who helped invent the test. Mike Syslo of the State Lobster Hatchery and Research Station in Vineyard Haven, Mass., hopes that use of the new test will provide enough evidence to prosecute the chlorine dippers.