A former seaport museum president pleaded guilty Monday to skimming $1.5 million from the institution to buy a carriage house for his Cape Cod home, art, jewelry and even a root canal.

John S. Carter, 57, of Osterville, Mass., falsified invoices to get the Independence Seaport Museum in Philadelphia to pay for it all, according to prosecutors. He pleaded guilty to two counts of mail fraud and one count of tax evasion.

Prosecutors said Carter spent more than $335,000 in museum funds to build the carriage house and make other property improvements. He also used about $50,000 to buy a wooden eagle that once decorated an old riverboat and a 19th century tusk from a narwhal, an arctic whale, authorities said.

Messages left with Carter's attorney, Mark Cedrone, and federal prosecutors were not immediately returned Monday.

Carter was the museum's president for 17 years before he was fired last year. Museum officials say Carter's misuse of museum money dates back to 1997.

In a lawsuit filed against him in January, museum officials accused him of defrauding the institution of $2.4 million. That lawsuit is pending.

The museum is located along the Delaware River waterfront. It owns the Spanish-America War cruiser USS Olympia and the World War II-era submarine USS Becuna, among other vessels.