WATERVILLE – Colby College is receiving as a gift a private art collection valued at more than $100 million that includes works by such greats as Winslow Homer, Edward Hopper and Georgia O’Keeffe, the college announced Friday.

The 500 paintings, prints and sculptures from Colby supporters Peter and Paula Lunder represent one of the most important collections of American art ever to be donated to a liberal arts college, Colby President William D. Adams said in a statement.

Museum Art Director Sharon Corwin said the collection includes 201 etchings and lithographs by James McNeill Whistler, making it the largest single collection of art by Whistler to be given to an American academic museum.

“In a single stroke, the museum will become one of the world’s most important repositories of Whistler prints,” Adams said. He said the gift places the college “among the nation’s best museums for the exhibition and study of American art.”

The formal announcement was communicated to college employees and other members of the community via e-mail Friday. The collection represents the largest single gift to the private liberal arts college, said spokeswoman Ruth Jacobs.

Elizabeth Broun, director of the Smithsonian American Art Museum, said the art collection “would be a landmark gift for any museum in America.”

“With this stellar Lunder collection, Colby College students will have a rare opportunity to learn the true power and meaning of art through study of the absolute best examples,” Broun said Friday in an e-mail.

The 24,000-square-foot Colby Museum of Art, which was founded in 1959 and features more than 5,500 works focusing on American and contemporary art, will undergo an expansion to accommodate the permanent display of the Lunder collection, Adams said.

A new wing will be built, with a planned opening in 2013, he said. The museum will celebrate its 50th anniversary in 2009 by exhibiting about 200 works from the collection.

“We believe these artworks offer both a window into the American experience and a broad perspective on the world, and we wish to share these opportunities for insight and enjoyment with others,” the Lunders said in a statement.

Peter Lunder is a 1956 graduate of Colby and former president of Dexter Shoe Co., which was owned by his uncle, philanthropist Harold Alfond. He and his wife began collecting European paintings in the 1970s and moved to American art in the 1980s.

“As collectors,” Broun said, “the Lunders were fast learners, determining early on that they would pursue only the very finest artworks. They studied seriously, consulted broadly, and sent out the signal that they wanted the best, so they saw most everything of significance that came on the market over many years.”

In addition to being a collector, Peter Lunder serves on the Smithsonian’s National Board, where the Lunder Foundation endowed the Lunder Conservation Center and the Lunder Education Curator at the American Art Museum.