BY MARILYN CALDWELL Marilyn Caldwell, a Los Angeles teenager, reported the Beatles' recent visit for The Times.     The four most successful hermits I know are led by a chap named Peter Blair Denis Bernard Noone. To millions of teen fans he is just plain Herman, the 17-(soon to be 18)-year-old leader of one of THE top pop groups on the scene today.     The five boys, Peter, Keith Hopwood, Barry Whitwam, Karl Green and Derek (Lek) Leckenby, were recently imported from England to do a movie for MGM, and when I learned that they would be staying in a private home in Benedict Canyon, I decided to have a go at arranging a personal interview with them. Hermits' lair     After several weeks I finally discovered the much sought-after telephone number of the house in the canyon.     I immediately phoned and spoke first with Charlie Silverman, the boys' road manager. He handed the phone over to Peter (Herman), who said that I could surely have an interview at the house, and I could stay for dinner as well if I liked. I liked!     The following night, Tuesday, was the most convenient. So, armed with paper and pencil and a somewhat nervous appetite, I headed for the Benedict Canyon. The house happened to be the same one occupied by the Beatles during their late August invasion of Los Angeles, and I, like the many other Beatle and Hermit fans, was curious to see what it was like. Busy Guard     There was a guard, of course, and a small crowd of about 10 girls to keep him busy. He was a little wary of letting me by, as he hadn't been told I was coming, but the mixup was quickly settled, and I finally found myself on the other side of what had seemed to be an unconquerable gate.     While I waited for the boys I had a chance to glance at the house. It was styled and decorated in what you might call 'modern western', with wooden beams in the ceiling, wood paneling and a huge brick fireplace in the main living room where I was sitting. I could see that the house was horse-shoe shaped with a beautiful swimming pool located in the middle area. I learned later that the bedrooms (there were six of them - each with its own bathroom, dressing room and fireplace) were located in one wing, while a game room (including a pool table, a poker table, and a miniature player piano) and a room called the Corral (with a huge bar all done in cowhide) shared the other wing, and the living room, dining room and kitchen were located in the middle.

We had lamb chops for dinner. I wasn't really hungry. I was content to just sit and absorb the boys' witty Mancunian humor and thick Lancashire accent. It was a treat just to listen to them.     They were plenty hungry, though, and I understood why when I asked what a normal non-working day was like for them. Peter's Pastime     Peter's favorite pastime was riding around on his motorbike, going most anyplace - once to Malibu and occasionally to record shops.     The others, Karl especially, enjoy horseback riding very much, and they went riding as often as they could. They rode in Griffith Park, and spent one day on a ranch.     "While at the house," Peter told me, "we usually swim, play pool, and listen to records, and sometimes we have a 'friendly fight' and throw our road manager in the pool with his clothes on!"     The lads had had several parties, including one for their parents who all came out to California, "for a fortnight," as Lek puts it.     After dinner the boys had to leave to attend a movie preview. Peter suggested that I come again the following night to finish the interview and said I could stay for a party planned for that night too, if I cared to - I cared to!     That night, not too long before his party guests were to arrive, Peter was up at the gate giving fans rides on his motorbike! When I finally had to leave, he aplogized for not having had the chance to talk to me more. I didn't really mind.     So on the group's last night in Los Angeles before flying to Chicago, I was invited to the house again to finish the interview.     Keith, who likes to read while on tour, was found sitting on the sofa, deeply engrossed in "The Three Musketeers" (what's that - a new group?" Peter joked.) We had a great time making the movie," Keith said. "The only bad part was waiting around between takes. we would work from 6 till 6 and towards the end we would get pretty tired."     The house was equipped with two telephones, and both were ringing constantly whenever I was there. Every once in a while Peter would answer one of them and greet the unsuspecting caller, who was almost invariably a giggling teenage girl, with anything from a Chinese to an Italian accent. His favorite greetings included "You rang?" and "Hello, Hollywood Mortuary." Finally, in order to complete the interview, he had to take both phones off the hook for a while.     I asked Peter how long the group's success had been growing. "About a year," he answered. "I'd like it to keep going for about another 25 years, and then get married."