TRIBUTE (PG) -- At the AMC Carrollton, Aspen Hill, Jenifer Cinema, Loehmann's Plaza, Roth's Seven Locks, Roth's Tysons Corner and Springfield Mall.

The discrepancy between generations in "Tribute" has the following line-up:

A father, played by Jack Lemmon, who is given to dressing up in a chicken costume and pouncing on people, who had driven away his wife because he was never able to stick to a job or resist the lures of prostitutes, and who makes a marginal living -- his bosses subsidize his fancy house -- as a fast-talking flack, whose specialties are practical jokes and dirty talk.

His son, played by Robby Benson, who enjoys photography, museums and history, and is getting a doctorate in preparation for a career as a teacher.

Guess what the problem is?

It is not filial duty, although the son is understandably reluctant to spend time with a man whose idea of fun is a This-Is-Your-Life banquet for a call girl and her clientele, and whose tricks include having one of his own cast-off pickups conceal their relationship and pretend that she has fallen in love with the son. On finding out that the father has cancer, the son submerges his own feelings to do everything he can for the pathetic old jokester's comfort.

No, the problem is that the son must be shaken loose from his "uptight" ways, dislodged from his unnatural propensity for such things as museums and history, and taught to have fun, as exemplified by the feverishly sordid pursuits of the father. "The kid wants to teach history!" says the father with a vicious sneer, indicating that the boy must suffer from a near-criminal hypocrisy because he doesn't want to pursue low life with him.

A chorus of respectable types -- Lee Remick, as the boy's mother, Colleen Dewhurst as the father's doctor, John Marley as his business associate -- keep claiming that the antics of this silly creature are a major source of joy to the world. They are remarkably unconvincing.

But the strongest case against the story line is made by Lemmon himself, whose performance as a physically ravaged and emotionally desperate man is so vivid as to make it an act of charity for those who know him to keep alive his sad little delusion.