When James Southers went to work for Vision Hosiery Mills in Belmont in 1942, stockings came only in about a dozen shades of beige, black and tan with names like Merry Widow and Hurdy Gurdy.

They had the customary seam down the back - if you could get them. Back then, nylon was in short supply, having been drafted for the war effort for use in soldiers' parachutes.Today, machines can produce up to 156 colors of seamless hose.

Times have changed for the hosiery and sock industry. Mr. Southers, now vice president of manufacturing for Vision's Knit Products Corp., even remembers pantyhose for pro football players a few years ago.

It was an idea whose time had not come yet, Mr. Southers says.

Despite such glitches, the $6 billion industry is doing well. Exports are up, imports are down and production is booming.

Roughly 90 percent of the hosiery industry's domestic production is in the Carolinas, Alabama, Georgia, Kentucky and Tennessee. It has seen major manufacturing and marketing changes in the last 20 years.

The biggest single change was pantyhose, says Mr. Southers of the one- piece undergarment that caught on with women about 1970. It put a lot more people to work. Today, Mr. Southers' company is the only U.S. manufacturer of Christian Dior women's hosiery. Mr. Southers browses through women's hosiery

sections of department stores twice a month to see how the Dior line is doing against competitors.

The 1970 introduction of L'Eggs, the pantyhose packaged in a container with an egg-shaped top, put pantyhose in gasoline stations, drugstores and supermarkets as well as department stores.

In the last decade, innovation has come quickly:

* A sock for every imaginable sport.

* Socks with pads in the soles.

* Shops that sell nothing but socks.

* Hose in a lighter weight known as summer wear.

* A comfortable hose made of spandex and nylon.

The industry now has hitched its future onto the use of computers and the greater speed of the equipment.

Mills now are able to change styles in minutes with the help of computerized disks. Bar computers are linking hosiery manufacturers with retailers for quick delivery.

Until we got into computer pattern changing and computerized machines, that wasn't possible, says Sid Smith, president and chief executive of the Charlotte-based National Association of Hosiery Manufacturers, the industry's trade group.

At Knit Products, bar coding helps the company keep track of its inventory by size, color and style of hose, Mr. Southers says. It also enables the company to ship out products faster to customers who have similar systems.

Some manufacturers even want consumers to get into the computer act. Two months ago, Sara Lee, makers of Hanes and L'Eggs hosiery, began a yearlong test that allows shoppers to buy pantyhose by size and color using a computer.

The increased proficiency has helped the industry fend off imports, a nagging problem for other segments of the textile industry. Socks and hosiery account for about 6 percent of the $100 billion textile and apparel industry.

After five straight years of import growth, imports fell about 1 percent in 1987 to just under 12 million dozen pairs of hosiery and socks, accounting for only 3.7 percent of the U.S. hosiery market. Of that, 59 percent was in socks.

At the same time, hosiery exports jumped 43 percent to 5.636 million dozen pairs last year, aided in part by the lower value of the dollar, which makes U.S. goods cheaper to buy overseas.

Mr. Smith explains the turnaround this way: We're threatened by imports like anybody else. (But) we've looked at the competition . . . and said, 'What's it going to take to beat them?'

A lot of people think Washington is going to make us (the United States) competitive. But our industry looked at the whole situation and said the answer to us being competitive is going to come within the four walls of our plants.

While the industry is having some good times, there are some concerns.

Some executives worry about being able to attract workers in the future.

As equipment becomes more sophisticated it's going to take higher skilled people to operate it, says Charles Stowe, president of Belmont Hosiery Mills Inc. That's been a problem for a long time.

Despite recent mergers and consolidations, experts say the industry is still mostly made up of small companies, particularly in the sock segment. Over the last four years, the number of hosiery companies has gone from 283 to 328.