Who knows what kind of adventures await us in the afterlife?

Most folks, when faced with their mortality, like to imagine pearly gates and little cherubs plucking harps on a cloud.

Jon Kenoyer, a retired mailman who died March 6 at his home in Santee, Calif., was a selfless type. He wanted only for his body to be donated to a medical research firm in Allentown, Pa., to help cure Alzheimer's, his family said.

So there was plenty of surprise to go around yesterday morning when Kenoyer's body showed up at Pets Plus USA, in Northeast Philadelphia, where employees were awaiting the arrival of some tropical fish.

"At first, I was completely shocked when I got the phone call," Kenoyer's widow, Mary, said during a phone interview last night.

"Then I started laughing a little when I hung up the phone. Jon was a practical joker, and I thought, 'He's pulling the last joke on us.' "

It took hours for law enforcement and other agencies to sort out the bizarre odyssey that Kenoyer's body took.

A Pets Plus employee went to a US Airways cargo facility near Philadelphia International Airport Monday night to pick up a shipment of tropical fish that were supposed to be separated in three packages, said police spokesman Lt. Frank Vanore.

Security guards told the employee that he didn't have the proper credentials to make the pickup. First thing yesterday morning, Pets Plus owner Mark Arabia sent another employee back to US Airways.

"Someone in the cargo area put one long box in the back of [the employee's] Jeep Cherokee and told him, 'It's yours,' " Vanore said.

It didn't take long for Arabia and his employees to realize that they had a casket at their large and colorful pet store, on Roosevelt Boulevard near Red Lion Road.

Vanore said that police arrived at the store about 2 p.m. and returned the casket to the airport. It was expected to be shipped to its intended destination, LifeQuest Anatomical, in Allentown.

Arabia, who could not be reached for comment last night, told TV reporters earlier in the day that he thought the mix-up was "horrible. . . . If it was my family member, I'd be really broken up."

US Airways, in a statement, said that the mix-up "occurred due to a verbal miscommunication between a delivery driver and the cargo representative. We are working to rectify the situation and are deeply sorry for the inconvenience this has caused."

Mary Kenoyer said that her husband died unexpectedly last Friday of complications from early-onset Alzheimer's. "He just stopped breathing," she said. "I still can't believe he's gone."

The couple, who had been married for 40 years, had agreed to donate Jon's body to LifeQuest. The firm will send his cremated remains back to California later this week, she said.

Kenoyer tried to make the best of the media's fascination with her husband's posthumous pet-shop visit.

"I said, 'Let's turn this into a positive. We can get the word out about the disease, and the need for a cure.' " *