WORTH NOTING ON TV
This guide is designed to alert readers to the scope and variety of programming coming up. Listing is not meant to represent blanket endorsement. Viewers are urged to be selective. FRIDAY
The River Niger (Arts & Entertainment/cable, 8-10:30 p.m.): Top American actors Cicely Tyson, James Earl Jones, and Lou Gossett Jr. star in film version of stunning ghetto drama.
SATURDAY
Pan Am Games (CBS, 1 p.m.; also Sunday noon): Olympic-style sports competitions from Indianapolis.
Evening at Pops (PBS, 8-9 p.m.): Marvin Hamlisch, Gregory Hines, Manhattan Transfer, Itzhak Perlman, and Buddy Rich join John Williams and the Boston Pops Orchestra for a gala evening.
Sentimental Swing: The Music of Tommy Dorsey (PBS, 9-10:53 p.m.): Mel Torm'e is host for an all-star Hollywood Palladium tribute.
SUNDAY
On the Edge of Extinction: Panthers and Cheetahs (PBS, 8-9 p.m.): National Audubon Society special reports on two of the world's most endangered big cats.
Elvis (Cinemax/pay cable, 9-10 p.m., repeated Wednesday, 7 p.m.): Vintage clips, stills, and home movies of ``The King.''
MONDAY
The Congo With Michael Wood (PBS, 8-9 p.m.): Repeat of ``River Journeys'' segment on a 1,000-mile journey up the Congo River in Africa.
Swingin' Over the Rainbow With Willie Nelson (PBS, 9-10:49 p.m.): Repeat of concert of Willie and his family band performing favorites from his ``Stardust'' and ``Somewhere Over the Rainbow'' albums.
TUESDAY
Antarctica: The Last Continent (PBS, 10-10:50 p.m.): Documentary on the bleak but beautiful continent that opens to exploitation when international treaties end in 1991.
WEDNESDAY
Lions of the African Night (PBS, 8-9 p.m.): Repeat of National Geographic special about a pride of 30 lions during a night in the bush.
A Musical Toast: The Stars Shine on Public Television (PBS, 9 p.m.-midnight): Repeat of fund-raising gala featuring such stars as Marilyn Horne, Bernadette Peters, and Leonard Bernstein.
THURSDAY
Local Hero (CBS, 9-11 p.m.): Superb whimsical satire, directed by Bill Forsyth, about the comparative changes in life styles of American and Scottish citizens when money is at stake.
Our World (ABC, 9-10 p.m.): One of 1987's best series, now canceled, repeats the program that recalled the fall of 1962 and the Cuban missile crisis.
The Man Who Loved Birds: The Story of John Bax (PBS, 8-8:50 p.m.): Documentary about a photographer who filmed birds of North and South America.
Listings are in Eastern time; other zones may vary. Please check listings for all PBS programs, since local option often results in differing days and times.