Andrew Sozzi remembers his days as a mail carrier, making his way up Central Park West early on Monday mornings, his keys jangling and each mailbox he opened spilling over with more than just letters and bills. ''They would be teeming with wallets,'' he said. ''I guess it makes sense after all the action in the park on the weekends.''

Like mail carriers around the city, Mr. Sozzi sent the wallets -- and other undeliverable items like ''guns, hypodermic needles, a dead cat and once, a two-pound bar of chocolate which melted all over the mail and attracted an army of ants'' -- to the short-paid office at the Postal Service's Morgan Processing and Distribution Center, at Ninth Avenue between 28th and 30th Streets. The office receives 100 to 200 wallets a week, most missing cash, credit cards and other valuables. If a wallet contains the owner's address, it is returned. The Postal Service pays the postage for all but the largest wallets.

Emma Edwards, 50, one of about 20 people who works in the office, has seen thousands of wallets -- and plenty of other things. ''We once had a crate of crickets arrive and no one was too excited about it because we all thought they were roaches,'' she said. ''I suppose my favorite was the tadpole that arrived in a Baggie. We all brought it fish food and kept it alive for about two months. It was good for morale.''

Barbara Felder, 51, picked through a worn leather wallet searching for an address. ''I constantly think about the fact that I'm handling people's most personal things,'' she said quietly. Occasionally she will call a number on a business card to track down an owner if there is no formal identification. ''It really makes me sad when I go through a wallet that may have family snapshots but no address,'' she said. ''I know in my heart it may be the last photo they have but there's nothing I can do.''