"Nicky Dirt," "Johnny Trim," "Big Nose," "Fat Michael," "Skinny Michael," "Benny Eggs," "The Colonel," "The Count," "Don Cheech," and "Cheese."

These are some of the characters in a cast of hundreds from the latest Mafia show in New Jersey, produced by the state attorney general's office. The noms de guerre popped up in secretly taped recordings of alleged mobsters, played at pretrial hearings in the past month.

In the first court case of its kind in the nation, the prosecution is trying to prove that there is indeed a Mafia and that eight reputed members of the Vito Genovese crime family, most of them from resort towns on the central New Jersey shore, committed a string of crimes as members of a nationwide mob conspiracy.

The 60 hours or so of recordings, made with court-approved wire taps, room bugs and on-body devices in 1977 and 1978, are invaluable to public understanding of the Byzantine world of the New Jersey Mafia. But the picture that emerges from the tapes is not one of a coolly efficient band of underworld masterminds, as the state is trying to portray. The Mafiosi reveal themselves as thoroughgoing misfits and braggarts, but very scary types just the same.

Their chiefain was Anthony (Little Pussy) Russo, a blabbermouth who talked to almost anyone including some reporters, about his strongarm activities. The taped Russo dropped names of dozens of police officials, politicians and businessmen he claimed to have in his pocket, but state investigators said they found that most of his claims were false.

"Little Pussy" -- the name dates to his early years as a cat burglar -- surely deserves the mob's Rodney Dangerfield award for his performance. Obsessed with lack of "respect" from colleagues and underlings alike, he repeatedly demanded tribute from minions who never got around to ponying up. h

An illiterate, Russo spun off malapropisms worthy of Flip Mahoney in "The Bowery Boys," repeatedly telling -- for example -- of putting bank assets "into escarole."

Russo was slain gangland-style in his apartment last April, shot four times in the head. Police never solved the murder, but more or less conclude that his mob associates feared his scatterbrain nature would eventually lead him, fumbling all the while, to help the state police crack this wideranging case.

The prosecution alleges that Russo's underlings included "Pee Wee," the 4-foot-7 alleged numbers boss who screamed polysyllabic profanities when frustrated, and Russo's young alleged enforcers, who were heard smoking a controlled substance when out of sight of Russo, who didn't approve of recreational drugs.

One of the enforcers, heard to brag without end of his manly performance with women, was bisexual, according to sources -- the first alleged mobster in that category, by all accounts.

As recorded on the tapes, the enforcers' routine in extorting from businessmen was, on the whole, discreet. No direct threats. Instead, they talked of "guys from New York" who might look up businessmen if the money wasn't paid.

"They're animals," one of the defendants warned a contractor, referring to the New Yorkers. "Ruthless."

It became clear in the recordings that there were, in fact, no "guys from New York" -- it was a ruse by some not very convincing guys from New Jersey.

Ragtag as they were, the mobsters were involved in an impressive list of crimes, including the operation of a large numbers ring in North Jersey, extortion, robbery and the murder of an alleged Trenton mobster for having shot another Mafia associate, the prosecutors claim.

The state's best evidence is on the Russo gang's loan-sharking. A building contractor wore a microphone in a jock strap at meetings where the enforcers threatened to break his legs and make his children "fatherless" unless he kept up payments of his 150 percent yearly "vig," or interest.

The tapes also reveal apparent mob interests in a wide range of legitimate businesses, from restaurant chains and seashore resorts to real estate developments.

The authorities also learned a lot about the configuration of the nationwide mobs. They were helped in this not only by Russo's garrulousness but by his familiarity with many top mobsters around the country from his days as chauffeur to Vito Genovese, once the Mafia's "boss of all bosses."

In some of his most unguarded moments, Russo chattered away about mob attempts to infiltrate casinos in Las Vegas. Federal and state officials have taken notes.

Russo said repeatedly that Anthony (Tony Pro) Provenzano and Matthew (Matty the Horse) Ianniello secretly run one casino. Provenzano, a longtime Teamsters Union leader in New Jersey, is now serving a 20-year federal sentence for racketeering. Ianniello, reputedly Manhattan's leading loan shark, controls many midtown Manhattan bars and restaurants, according to law enforcement officials.

Revelations in the tapes have already prompted federal indictments of six men. Two of Russo's associates where charged variously with holding hidden interests in the Jolly Trolley Casino in Las Vegas and with skimming profits from the casino. Federal investigators also charged that a former Las Vegas police detective took bribes.

The big fish in both the U.S. case and New Jersey's Mafia conspiracy case is Ruggerio (The Boot) Boiardo, 89, a reputed capo regime in the Genovese family who earned his nickname as a bootlegger in the 1920s.

He is charged with ordering the murder of Trenton mobster Paul Campanile and a robbery and overseeing an extortion ring, as well as with conspiracy as a Mafia member. His lawyers contend that Boiardo is too physically and mentally feeble either to be a mob captain or to stand trial.

But a recording of a June 12, 1978, conversation in a Newark luncheonette shows Boiardo alert and forceful. He tells Russo, "I'm the boss," and scolds him for losing his grip on loan-sharking and casino-skimming operations.

"We'll be taking a lot of criticism for putting an 89-year-old man on trial," said a top New Jersey law enforcement official. "But we think a man who can order another's murder is a dangerous man."

Perhaps harder to prove than Boiardo's competency will be the state's main contention -- that there exists a Mafia or Cosa Nostra, described in the indictment as a "nationwide criminal organization used by its members to commit crimes and maintain power over rivals and victims."

There are still some people -- criminologists, newspaper columnists and even some law enforcement officials -- who doubt that there is a Mafia. FBI Director J. Edgar Hoover denied there was a mob for the last several decades of his life.

Most other federal law enforcement officials believe that the U.S. Senate's organized crime hearings in the late 1950s proved there was a Mafia.

The busting up of a nationwide meeting of the mob at Apalachin, N.Y., in 1957, seemed further confirmation, as did the subsequent congressional testimony of Mafioso Joseph Valachi.

Though the current case has generated considerable publicity, many New Jerseyans think trying to prove the existence of a New Jersey Mafia is like trying to confirm through the rules of evidence the existence of the New Jersey Turnpike.

One newspaper columnist here wrote that by telling us that there is a Mafia after all -- in 1980 -- New Jersey Attorney General John Degnan might as well assert, 250 years after Newton, that "things generally fall downward."