He turned a dial on an instrument that looked like a radio. A deep, resonant drumming started. "That's the heartbeat of one on the bottom. This guy will hear it and come out."

After a long moment a strange creature backed from the shell, tail first, cautiously, still attached to the shell it wore. It was wrinkled and shiny, with two long tubes ending in eyes, a trunk like an elephant, a snorkel mouth, and a pointed tail. "They also come out to eat. Sometimes he eats carrion, but he makes great chowder, just the same."

She grimaced. "Not for me, he doesn't. But you don't catch them, do you?"

"I count them. Count 'em and tag 'em and shoot 'em on film with a strobe light to prove we did the job. Hour after hour, day after day." He shrugged. "It's a living, I guess." He switched on an enormous photographer's strobe light, in a bright yellow underwater case. It whined and squealed as it built up a charge in its condenser.

"High-tech. Look at this thing: With ths little trigger I can light up the world." He showed her a stainless steel cylinder with a trigger on it. "Sometimes we leave a camera with a colony on the bottom, and a strobe light, and take their pictures to see what they do at night."

He pressed the trigger. She heard two beeps from somewhere deep in the hull. The strobe flashed, turning the cabin bright blue and blinding her, as if lightning had struck.

He sighed. "Their sex life stinks, but I can give you the conch population of every reef between here and New Providence: mommas, daddies, and all their little kids."

"But why?"

He looked miserable. "Because the Ministry of Fisheries thinks we're helping the economy. Because we have a grant."

He pointed to the conch on the table. It had somehow inched almost to the edge. "You ought to see them traveling on the bottom. Big ones first, then the little ones, lined up like elephants in a circus parade." He rescued the cliff-hanging conch and put it in the center of the table, on a chart. "This job can get old, you understand. Day after day, hour after hour. Conches on parade..."

She was sure that there was plenty of work for marine biologists in laboratories and classrooms. If only she could convince him not to dive. She tried to keep her voice steady. "It sounds... well, beneath you, Mike."

He grinned and pointed down. "It is. It's all down there."

"That isn't what I mean, and you know it."

"I love the bottom of the ocean, Mom." He prodded the creature. Startlingly it leapt from the chart table and crashed against the tank. He picked it up. "But conchs? You're right, they're a pain in the butt." He glanced at her. "I'll tell you one thing about this little bastard, Mom."

"Yes?"