The police normally withhold the names of minors who are accused of crimes, but officials said they made public the names of the youths charged in the attack on the woman because of the seriousness of the incident. Met at 8:30 P.M. Investigators said preparations for the crime spree apparently began about 8:30 P.M. Wednesday, when 17 youths gathered outside the Taft Houses project at 117th Street and Madison Avenue.  ''This is a prearranged meeting,'' Deputy Police Commissioner Alice T. McGillion said. ''We think this is the group that decides they're going to go out 'wilding.' But as they're walking south down the street, they run into another group of 15 kids at Fifth Avenue and 110th Street. That, as far as we know, was not prearranged.''  Three of the youths charged in the attack on the investment banker, along with the 13- and 14-year-olds charged in the attack on the male jogger, were apprehended by a police anti-crime unit as they were leaving the park at 100th Street and Central Park West at about 10:40 Wednesday night. Several hundred yards away, at 1:30 A.M., the investment banker was found, unconscious and bleeding, by two passers-by.  At the time the five youths were apprehended, Commissioner McGillion said, patrol officers at the Central Park Precinct had received two telephone calls from the couple on a tandem bicycle about a roving gang of youths in the park, and had sent radio cars to 110th Street and the East Drive to look for them. But the youths had disappeared by the time officers arrived, the police said. The second call from the same couple had sent cars and anti-crime units rushing to 98th Street and the East Drive, but again, officers found nothing.  The precinct had also taken a report from the 52-year-old jogger, who went to the station house at 9:10 P.M. and said that he had been punched by some youths near the West Drive and 102d Street. No Evidence of a Leader  But it was not until the investment banker was found that officials began to realize the gravity and extent of the crime spree.  ''I don't think that they had in mind to go into the park and rape someone,'' Chief Colangelo said, adding that the police had uncovered no evidence of a leader or leaders in the groups.  ''We believe that there may have been other incidents in the park that night,'' Chief Colangelo said, adding that the police had established a 24-hour hotline for victims or witnesses to call. The chief said the police would respect the wishes of those wanting to remain anonymous. The number is (212) 598-0071.  ''It took some time to realize that all the incidents were connected,'' the chief said. ''Some time had elapsed from the first incident to the last. And remember, this was nighttime, the park has a lot of dark, secluded areas - and some of the statements we have indicate that the youths were lying undercover, waiting for a victim.  ''I'm not sure we have all the answers now. It's been a slow process to try to put all the pieces together.''  Chief Colangelo added that legal restrictions on the police in questioning minors had compounded the investigators' burdens. Those less than 16 years old who are taken into custody must be questioned only in specially designated rooms, and their parents must be present.  Asked how the arrested youths had acted after their arrest, the chief declined to offer details. ''Some of them feel the seriousness of the cases,'' he said, ''and some of them not so seriously.''  Chief of Detectives Robert Colangelo announcing the arrests of four youths in connection with the rape and beating of a jogger in Central Park. At left was Aaron H. Rosenthal, head of detectives in Manhattan (The New York Times/John Sotomayor)
LEAD: The youths who raped and savagely beat a young investment banker as she jogged in Central Park Wednesday night were part of a loosely organized gang of 32 schoolboys whose random, motiveless assaults terrorized at least eight other people over nearly two hours, senior police investigators said yesterday.