NEWARK, N.J. - He's been dubbed "the Mad Hatter," but his eight-month string of bank robberies has been anything but a tea party for authorities in central and northern New Jersey.

The middle-age bank robber known for his wide range of head gear struck again Wednesday when he came in out of the rain long enough to knock off a Commerce Bank in Metuchen and flee with an undisclosed amount of cash.

That raised the number of banks he has victimized to 15 since September: seven in Union County, five in Morris County, two in Essex County, and one in Middlesex County, according to the Union County Prosecutor's Office. Eleven have been Commerce offices. His haul is well over $60,000.

Almost as extensive as his choice of banks is his choice of hats: a hunter's cap in one robbery, different types of baseball caps in others, a fisherman's hat in still another heist.

Authorities have described him as a white man between 45 and 55 years old with gray hair, about 5-foot-10 and 180 pounds, and a medium build. He has worn gold-rimmed prescription glasses in most of the robberies. At various times he has worn flannel shirts, painter's pants and a blazer.

He has been caught numerous times on bank security cameras from several different angles. Authorities say he is average-looking enough to blend in with the rest of the customers in the suburban communities in which he has operated.

"This man is hiding in plain sight," Union County Prosecutor Theodore J. Romankow said. "What is remarkable about him is that he is unremarkable."

In contrast to the group of four bank robbers whose capture last month led to the accidental shooting of FBI Special Agent Barry Lee Bush - and whose tactics included shooting automatic weapons and leaping over countertops - the Hatter has operated quietly, usually giving a teller a note demanding money and then leaving without attracting the attention of other customers.

He was the subject of a TV segment on America's Most Wanted that aired twice in March and once in April, but authorities said the show generated very few leads.

Serial bank robbers are not uncommon in New Jersey.

In November, a Camden man admitted robbing six banks in South Jersey over five months. And in February, a Connecticut man pleaded guilty to robbing three banks in the Garden State in addition to 22 more in four other states.

One of the nation's most prolific bank robbers was Cazzie Williams, a postal worker from East Orange dubbed "the Puffy Cheek Bandit." He admitted robbing 18 New Jersey banks - and 27 overall - between 1998 and 2000. Williams received a 13-year prison sentence.

Authorities are appealing to the public by offering a reward for information leading to the Hatter's arrest. The rewards are being offered by Crimestoppers, which operates anonymous tip lines in Union (908-654-TIPS) and Morris (973-COP-CALL) Counties.