When Steven McCormick was a law student, he asked a professor to explain the exact meaning of the word perpetuity. The law professor's reply to the young student was simple and direct. "It means forever - and a day," the professor said.

Forever and a day is exactly how long the farm fields will now be preserved at the Herring Creek Farm in Edgartown, and on the Vineyard this week Mr. McCormick, who is the president and chief executive officer for The Nature Conservancy, used the anecdote to drive home a clear message about what he called a new philosophy in land conservation.

"We are saving things forever, and what we are doing at Herring Creek Farm is on a huge scale," said Mr. McCormick.

On Wednesday afternoon Mr. McCormick addressed a luncheon for supporters of the international conservation organization. Held at the Hoft Farm in West Tisbury, the luncheon featured a litany of laudatory remarks about the Herring Creek Farm purchase.

The Nature Conservancy was the lead organization in the recent $64 million conservation purchase at Herring Creek Farm in Edgartown. The sale involved three other private buyers. The conservancy now owns about half of the 215-acre Great Plains farm, and plans are under way to launch a massive sandplain grassland restoration project on the 62-acre east field.

In an interview with the Gazette following the luncheon, Mr. McCormick compared the endangered sandplain community to the tropical rain forest.

"The sandplain natural community is one of the most diminished natural communities in the East - less than one per cent of the original sandplain exists today, so it's a very high priority, and while it may not have the same diversity and richness of species that the rain forest does, it's right up there with the rain forest in terms of how it has disappeared and what's left of it," he said.

Mr. McCormick began his work with The Nature Conservancy as an attorney in California in 1977. The California program is one of the oldest programs of the conservancy. Through the years Mr. McCormick moved up through the ranks, and in February of this year he was named president and CEO of the conservancy. Established in 1951, the conservancy is an international nonprofit organization devoted to the preservation of plants, animals and natural communities all over the world. Today the conservancy has a $1 billion national endowment and has protected more than 12 million acres in the United States.

Wednesday was Mr. McCormick's first visit to the Vineyard. "I don't want to leave," he smiled, seated in the shade near the old farmhouse. The Hoft Farm was purchased by The Nature Conservancy in 1997. It is now the field station for the conservancy program and the home base for an endangered plant propagation project.

At the farm on Wednesday, a display of educational material about the conservancy included a table with flats of mountain mint, New England blazing star, Atlantic joe pye weed and common evening primrose. Some of the endangered plants will be transplanted to the east field at Herring Creek Farm in the years ahead as the sandplain restoration project gets under way.

Mr. McCormick praised Tom Chase, director of the Islands program for the conservancy, and Wayne Klockner, director of the Massachusetts program for the conservancy, for what he called "out of the box thinking" on the Herring Creek Farm project.

"This project is the most expensive deal we have ever done, and it is the most highly leveraged. We didn't have to put any money into it," he said. "This is syndication for land protection and it's an important step - $64 million came from people who are not going to get $64 million in return. They've paid for it, and there is public benefit in that," he added.

Mr. McCormick said the two Islands are a high priority for The Nature Conservancy.

"Islands generally are biologically unique because they are cut off and they tend to develop their own plant species . . . . These aren't real big places, and they are under tremendous pressure," he said.