The Indians, who have crossed and recrossed this place longer than even they can remember, called it Pa-hay-okee -- Grassy Water.

It is one of the earth's unique regions, haughty and remote even under the onslaught of nearly a million visitors a year. It is a land of miracles -- the showy play of light on water, the awesome beam of alligator eyes glowing red in the night, the climate that tolerates both the desert-dwelling cactus and the 75-pound cowhorn orchid.

Everglades National Park is home to manatees and crocodiles; to sapodillas and water maccasins; to mosquitofish and ferociously carnivorous mosquitoes; to cotton rats, coots and cormorants. Today, as national parks go, it is not the highest or the tallest or the biggest. It has no grand -- or even great -- canyons, no purple mountain majesties.

But to Jack Morehead, who took over in late spring as superintendent of its nearly 1.5 million acres of sawgrass, pinelands, mangroves, hammocks and bayheads, there is splendor enough.

"Everyone keeps telling me I won't like it," says Morehead, who in his 27 years with the Park Service has worked in such national showplaces as Glacier National Park, the Grand Tetons, Mount Rainier, Lake Mead, and the Grand Canyon. "But just having the chance to see the sawgrass and the open spaces and those towering clouds, that's phenomenal. To me, it's just as interesting as those places out West."

Morehead's last assignment was the superintendent's post at Isle Royale National Park, a rocky 45-mile-long island in the middle of Lake Superior. It is a summer park, accessible only by boat or airplane, that plays host to maybe 17,000 warm-weather visitors.

By contrast, Everglades National Park drew 900,000 visitors in 1979. In the winter, some of them are campers who stay the two-week limit; the majority of summer visitors are day guests, many of them sunburned British, German and Japanese tourists on half-day tours.

"The other day at Royal Palm, a 9-foot-long alligator lay down right in the middle of the trail, and we had to rerout the visitors around him," says Morehead. "We're here to let the wildlife do what they want."

One night not so long ago, Morehead was driving alone between the park offices and Royal Palm, and, "I looked over to that side of the road, and that meadow over there was alive with fireflies. I just stopped and put on Fleetwood Mac and sat there and watched the show. In the Everglades, even in the grass there is splendor."

At 47, Jack Morehead had never even been to Florida before he arrived in May to take over from retiring Everglades superintendent John Good. He had beaten out as many as 100 other applicants for the job, which will pay him between $35,000 and $40,000 a year. He is known as a ranger's superintendent, someone who came up through the Park Service ranks and has gained a reputation as an expert in resource management.

"I think one indication of the service's confidence in Jack is the kind of assiggnments he's had before," says one National Park Service official. "Isle Royale is probably the finest example of a natural ecosystem that we have in the lower 48 states, virtually unchanged except by natural conditions and existing as it would have had man not interfered. He's experienced at balancing the public's interest with natural systems."

Born in Estes Park, Colo., the son of a self-made, bureaucracy-hating businessman, John Merl Morehead got his first job as a seasonal laborer in Rocky Mountains National Park and eventually earned a degree in forest recreation from Colorado A&M, now Colorado State University. He is a proficient mountain climber and snow skier who taught mountain warfare and wilderness survival to U.S. special forces during the Korean War. Accustomed to skindiving in Lake Superior's frigid waters, he thinks South Florida's tepid salt water feels like a warm bath.

At Everglades, he has inherited a $4.5 million budget, nearly 300 full-time, part-time and seasonal employes and a headache of a balancing act.

"I think what we have to do here is work out a compromise between pure conservation, which would allow nobody in, and uncontrolled public use, which would be disastrous," he says.

During the five or six years Morehead expects to be stationed at Everglades, his job will be to make sure the public gets optimum use of the park while insisting that its plant, animal and water resources be preserved for future generations.

The controversies already have come knocking.

One concerns an effort by South Florida's vocal hunter-airboat trail that cuts through parts of the Big Cypress Swamp and Everglades Park's northwestern zigzagging, stairstep boundary. Airboats, which are now banned within the park, are permitted in Big Cypress, and if this particular trail is reopened, they would inevitably be routed through a portion of the park.

Another issue Morehead must face is the proposed management plan for the 242 square miles of mostly wetlands known as the East Everglades. The plan was drawn up after two years of research by an interagency steering committee. It designates certain parts of the east Everglades for agriculture, certain portions for low-density (1 unit per 40 acres) residential use and an intermediate zone of uncertain seasonal wetness to be reserved, if conditions permit, for farming. At stake in the controversy are the area's fragile water table and the suravival of the endangered Cape Sabal sparrow, a neurotic creature that does not easily adjust to change.

As Everglades Park manager, the soft-spoken, slightly built Jack Morehead already finds himself at the center of both these issues, a target for the potshots of squabbling hunters, nurserymen, farmers, fishermen, no-use conversationists and property owners who are waiting to see where he stands.

"I haven't made any decision yet," he says. "I'm really looking at all sides."

In the 1930s, South Florida naturalist John C. Gifford wrote with expectant enthusiasm of the then-proposed Everglades Park, "It will be one place where the crocodiles, roseate spoonbills, ivory-billed woodpeckers and other creatures of land and sea may rear their young without molestation."

Today, the ivory-billed woodpecker is extinct, and the decisions Jack Morehad makes in the next few years could determine whether the Everglades as a whole survives.

"That's why about a quarter of our budget goes for research," says Morehead. Currently within the park, Park Service and private researchers are studying water quantity, quality and movement, vegetation, the habits of alligators and crocodiles and fire management.

On weekends, Jack Morehead trudges through the nature trails and hammocks of the Everglades to get a feel for his new turf. He says he is convinced that, like all other national parks, "the Everglades will become more and more valuable as time goes on. It will become more and more like a true museum, because literally we will face the time when all of Florida will be developed except the preserves, and people will come here to get away and be protected.

"This is the Everglades. There's nothing else like it. The stakes are very high."