Riding on Southern Railway's premier passenger train today is akin to a gathering of relatives around the death bed of a beloved but prominent family member.

In recent months, television crews, photographers, newspaper reporters and magazine writers have climbed aboard for the trip between Union Station in Washington and the Crescent city of New Orleans, or to intermediate Southern points with slowly-pronounced names like Poplarville, Purvis, Hattiesburg, Eutaw, Gastonia and Culpeper.

Other riders are individuals paying final respects to the last great passenger train in America operated by private enterprise. And there are many on board who are Southern Railway's own employes, taking advantage for perhaps the last time of free rides on the Crescent, a job benefit that applies to business and pleasure travel.

The trains are more crowded than usual, because of these personal service has taken something of a beating. Some riders wait several hours to be served dinners late at night in the dining cars, now without adequate staffs. The old passenger cars are not kept stainless steel-clean, as in earlier year. Upholstery is beginning to fray a bit around the edges.

The food still is superb with a distinctive Southern flavor (morning [WORD ILLEGIBLE] are the best and served in old-world dining-car ambiance with linen and fresh flowers. But the Southern Crescent is showing signs of terminal illenss.

One day soon, perhaps in a month or maybe next year, Southern Railway will stop operating its daily train between Washington and Atlanta - which travels on to New Orleans three days a week for transcontinental connections with Amtrak to California.

Few people expect passenger service on the Southern line to be dropped outright, in part because the Crescent provides the only rail travel to Atlanta - a metropolitan area with 1.8 million residents.

When the Washington-based railroad firm finally stops operating the trains, the Crescent will be taken over as part of the federally subsidized Amtrak system.The touches that have made the train something special will disappear as Amtrak - already awash in losses that have raised questions about the national passenger network of the future - moves to pare expenses to the bone.

Earlier this year, Southern announced plans to discontinue its one remaining train "only with the greatest reluctance," because of mounting losses. Southern claims the Crescent lost $6.7 million last year alone and $30 million since May 1971, when Amtrak started and Southern was among the handful of firms that elected to remain outside the government-aided system.

The Interstate Commerce Commission, a federal agency that must act on Southern's plans to drop the Crescent temporarily blocked the train's demise and recently concluded a series of hearings in 21 cities.

By Aug. 6, the ICC must decide if the Crescent can be stopped or if the agency will require Southern to operate the train for up to a full year. Within 12 months, the government is expected to make a decision on the question of the Crescent until the issue of Amtrak operating the Washington-Atlanta-New Orleans route is resolved.

In any event, it is unlikely the ICC will order indefinite operation of a money-losing train and there appears to be a Crescent in Amtrak's more limited future plans.

To Washington film-maker Chris Bedford, a recent rider on the Crescent between Union Station and New Orleans and a frequent rider of American trains, it won't be the same under government financing.

Bedford said he was one of those persons riding the Crescent now because it is doomed. "It could be the 1930s," he said, recalling train-window glimpses of Old South, as the Crescent moved down main streets of small towns west of Atlanta.

"The train cars are old, the blankets still have the original Pullman insignias, (roomettes) have fans and hot and cold running water, there's a buzzer and your shoes are shined at night if you leave them out in a special compartment . . . it's just really fantastic . . . the Pullman berths are really comfortable and you wake up and look outside . . . it's a very special treat," Bedford said.

On the Crescent, she added, "there is a concern for details you don't find on Amtrak . . . three or four people were waiting in Atlanta, repairmen, to see if things needed to be fixed, to check on linens . . . it's a very human way to go, with a scale and pace and a lot of values other transportation doesn't have . . . I can get work done, it's relaxing."

If Bedford emphasizes the practical value of rail passenger travel - and he predicts that in 25 years the automobile will have a far different place in American society, creating a need for rail services - many riders focus on nostalgia.

"When I was a child living in New Orleans. I would ride the train to Birmingham at least once a year. It's the best way to travel with children, and now I ride with my own children," said housewife Mildred Noel at ICC hearings in Birmingham.

"I would hate to see something that's meant a lot to me for 25 years come to an end," she added. Up and down the line, hundreds of other witnesses offered similar statements to ICC administrative law judge Helen Hoyt, who now must make a recommendation to the regulatory agency.

Hoyt must weigh these votes for nostalgia and a more relaxed way to travel against the firm's passenger losses and testimony from some shippers that they see no reason why freight rates should be subsidizing a relatively small number of riders (165,729 in 1977, up about 10 percent from the previous year).

Ross Capon, executive director of the National Association of Railroad Passengers, wants the Crescent to continue until an agreement is reached with Amtrak for continued service. It would be "senseless" to drop it next month and then restore service under Amtrak's name next year, he said.

Capon also charged that Southern claims of losses "are overstated or reflect unnecessarily expensive operating practices; that revenues could be increased with innovative pricing and marketing of services . . . that the improvement of this service is well within Southern's financial abilities."

Southern is one of the nation's most profitable railroads, with revenues last year of $1.14 billion and profits of $107 million. But Southern also is interested in expansion outside its routes in 13 southeastern states.The strategy of maintaining quality, but money-losing passenger service as part of good regional public relations has less attraction in an era of transcontinental rail mergers.

Not much longer will Joseph McMichael, a veteran passenger train sleeping room attendant; and bartender known to his riders as "Mac," provide a personalized touch of music taste as the Crescent rolls through the Carolinas. Symbolic of the former age when people like to ride the trains more often. Mac offers sippers of martinis and beer his own collection of good jazz on tape recordings. He said he doesn't much like the music of today, available on radio through the same speaker system.

On Amtrak, you're lucky to get Muzak.