Three novels and three short-story collections have been nominated for this year's PEN Faulkner Award for Fiction, the Folger Shakespeare Library announced yesterday.

The novels are William Gaddis' "Carpenter's Gothic," published by Viking; Larry McMurtry's "Lonesome Dove," published by Simon and Schuster; and Hugh Nissenson's "The Tree of Life," published by Harper and Row.

The short-story collections are "Later the Same Day" by Grace Paley, published by Farrar, Straus & Giroux; "The Christmas Wife" by Helen Norris, published by University of Illinois Press; and "The Old Forest and Other Stories" by Peter Taylor, published by Doubleday.

The winner will be presented with $5,000 at a ceremony May 10 at the Folger Library, and the five runners-up will receive $1,000 each.

"I'm going to spend it, you may be sure, right away," said nominee Peter Taylor, when asked how he planned to use his winnings. "I think I'll go to Venice."

The PEN Faulkner Award, supported by private and corporate grants as well as by proceeds from public readings, is billed as the nation's only literary prize given exclusively by writers. The judges this year -- its sixth -- are novelists Alice Adams, Richard Bausch and Beverly Lowry, who chose the nominees from more than 200 books published in 1985.

Past winners include Tobias Wolff, John Edgar Wideman, Toby Olson, David Bradley and Walter Abish.