Mr. Bloomberg’s effort this month to take Mr. Morgenthau to task was a public eruption of a feud that had long festered behind the scenes. It is a dispute that Mr. Morgenthau has contended is all about money and that the mayor and his aides say is about transparency.

Most of the money in Mr. Morgenthau’s accounts came from the settlement of criminal cases against corporate defendants. Mr. Bloomberg said the city was entitled to all of the money, and Mr. Morgenthau, leaving office in January after having served in the position since 1975, has sought to divide it between the city and the state, with a small portion going back to his office.

Mr. Post stressed that a great many of the other accounts the Finance Department found held small, even tiny, sums. Many  indeed most of the 781 accounts associated with the Department of Education  were what one official termed “bake sale” accounts for the Parent Teacher Associations, “coffee club accounts” set up by teachers’ groups or accounts for uniforms for sports teams.

More than 770 accounts containing $5.6 million were escrow accounts that held security deposits for property either leased by the city or from the city.

Mr. Morgenthau on Thursday said he was not surprised to learn of the other city unregistered accounts. Three of his four fellow district attorneys had already acknowledged using similar vehicles to hold funds seized or paid in fines.

“If everybody else has it, why are they picking on the D.A.?” he asked. “I felt the whole business was much ado about nothing.”

Mr. Morgenthau has contended that the city has long known of his accounts, from which, he has said, he paid out tens of millions to the city in recent years, $181 million this year alone.