The Fish That Lives Nowhere

The keeper had gone to find a longer net, and she had said, do not stick your hands in anything, and she had not come back.

Maya was counting sea cucumbers. There were supposed to be four in the log. She counted four. She counted them again and got four again.

"There's a fish that isn't on the list," she said.

"Where," said Soren.

"That's the thing." Maya crouched until her nose almost touched the glass. "I saw its head. Little pointy silver head. Then it was gone. There's nowhere for it to go. There's no rock, there's no plant, there's just sand and cucumbers."

Soren flipped to a clean page and started drawing the tank exactly as it was. Four brown cucumbers, lumpy as old potatoes, breathing slowly. Sand. Nothing else.

"Watch the fat one," Maya said. "Bottom left. Something's wrong with it."

"Wrong how."

"Its back end keeps opening."

They both leaned in. The cucumber's rear opening yawned wide, slow, the way a mouth opens when someone is falling asleep. Then it closed. Then, a minute later, it opened again.

"They breathe through there," Soren said. "I read it. Sea cucumbers pull water in through the back to get oxygen. So it opening isn't the weird part."

"The weird part is coming," Maya said. "Keep watching."

The opening widened. And a thin silver thread poured itself backward into the cucumber. Tail first. The pointed head went in last, and for one second the little fish looked out at them, one flat eye, before it vanished completely inside.

Soren stopped drawing.

"It went in tail first," he said.

"It went in tail first," Maya agreed.

"Nothing goes in tail first. That's backward. That's the hardest possible way to do it."

"Unless," Maya said, and then didn't finish, because she was watching the cucumber, which had closed up again as if nothing had happened. As if it had swallowed a secret and decided to keep it.

Soren wrote: fish enters host through rear opening, reversing, tail leading. Then he underlined reversing.

"Okay," he said. "Think about it from the fish's side. If you're a soft skinny fish with no shell and no teeth worth anything, and the whole ocean wants to eat you, what do you want more than anything?"

"A door nobody else can fit through," Maya said.

"A door that opens on its own," Soren said. "Every few minutes. To breathe."

They looked at each other.

"It's waiting for the breath," Maya said slowly. "It backs up against the opening and it waits. It can't force it. The cucumber's muscle is stronger. So it just holds on and waits for the cucumber to relax. And the second it relaxes to take a breath, the fish is already lined up. Tail first. So it slides straight in."

Soren checked it against the drawing in his head, then against the tank. The fat cucumber breathed. Nothing came out. The fish was still inside.

"That's why tail first," he said. "If it went head first it would have to turn around inside. There's no room to turn around inside a cucumber. So it goes in already pointed the way it'll want to leave."

"It parks itself," Maya said, and she laughed, delighted, the way she did when the world turned out to be doing something ridiculous on purpose. "It parks itself inside another animal's butt, pointed nose-out, ready to leave for dinner and come home again."

"Come home," Soren repeated. He liked that. He wrote: returns to same host. Then he stopped, because he didn't actually know that yet, he had only felt it was true.

"How do you know it comes back to the same one?" he asked.

"I don't," Maya said. "But you counted four cucumbers and there's one fish. If it swapped around, we'd have seen it trying doors. It didn't try doors. It went to that one. It knew which one was home."

Soren stared at the fat cucumber. And a thought arrived that he did not enjoy.

"Maya. What's the fish eating in there."

"It leaves to eat," Maya said. "You saw it wasn't hungry now."

"Some of them don't leave to eat," Soren said quietly. "I mean, I don't know that this one does that. But I read there are kinds that eat the cucumber. From the inside. The parts the cucumber uses to make babies."

The touch-tank pump hummed. The four cucumbers sat in the sand, breathing their slow backward breaths, and one of them had a fish inside it that might be a guest and might be something worse, and there was no way to tell from the outside which.

"So the cucumber's just carrying it around," Maya said. "Its whole life. And it doesn't know."

"It can't know," Soren said. "It doesn't have the kind of body that can know."

Maya was quiet. Not the excited quiet. A different one.

"There's a whole animal," she said, "that has never in its life lived anywhere that isn't inside another animal. Its whole idea of the world is the inside of a cucumber and the little trip out for food. That's the whole map. That's everything it's ever seen."

"And we almost logged four cucumbers and went home," Soren said.

"We almost logged four cucumbers and went home."

They did not stick their hands in the tank. They knelt on the cold floor with their faces close to the glass and waited, because if it had gone in to rest, then sooner or later it would have to come out to feed, and they both wanted to see the exact moment a fish decided to leave the only home it had ever known.

The fat cucumber's rear opening widened. Slow. Sleepy.

A pointed silver head came out first, testing the water, one flat eye turning to take in the enormous lit tank as though seeing an ocean for the very first time, every single time.