NEW MILFORD, Conn. (AP) _ Writer and literary critic Malcolm Cowley, who was one of the post-World War I ''Lost Generation'' authors that included Ernest Hemingway and F. Scott Fitzgerald, died Tuesday at age 90.

Cowley suffered what appeared to be a heart attack Tuesday morning at his home in nearby Sherman, said his nurse, Rhoda Joyner. He was taken to New Milford Hospital, where he died, said hospital spokeswoman Shirley Fredlund.

Cowley, a former editor at the New Republic, belonged to the group of American expatriates in Paris - including Hemingway, Fitzgerald and Ezra Pound - that Gertrude Stein dubbed the ''Lost Generation'' in the 1920s.

He is credited with being among the first to recognize the brilliance of those writers and with rescuing writer William Faulkner from obscurity.

''Cowley was a living bridge, both in his genial person and his engaging, shrewd criticism, with the generation that were young in the 20s,'' author John Updike said in a statement from his publisher, Alfred A. Knopf in New York.

''His reactions to and perceptions of Hemingway, Fitzgerald, Faulkner and (John) Dos Passos are invaluable,'' Updike said. ''He was an energetic and gregarious man who lived the life of the mind with gusto and good nature.''

Born on Aug. 24, 1898 in Belsano, Pa., Cowley attended Harvard University from 1915 to 1917, when he joined the American Ambulance Service in France. He re-enrolled in Harvard in 1918 and graduated cum laude in 1920.

While a student, he began contributing book reviews to the New Republic and Dial magazines.

After graduation he spent much of his time writing free-lance magazine pieces.

Cowley won a fellowship to study French literature in 1921-22 and again the following year in France, allowing him to hobnob with America's young expatriate writers. He returned to the United States in 1923.

At the encouragement of his friend Hart Crane, he compiled a book of his poems. The book, ''Blue Juniata,'' published in 1929, was enthusiasticall y received.

Nineteen other poems dealing with his alienated generation were later collected in ''The Dry Season,'' published in 1941.

In 1929, Cowley became literary editor of the New Republic. Among those he encouraged as writers was John Cheever.

While at the New Republic, Cowley published the book for which he was best known, ''Exile's Return: A Narrative of Ideas'' in 1934. The book dealt with writers of the 1920s who tried to pursue alternative lifestyles in Paris and Greenwich Village.

Some consider his most valuable contribution to be his editing of ''The Portable Faulkner'' in 1945, which saved Faulkner from obscurity.

''He did that at a time when Faulkner's books were still not selling,'' said Cleanth Brooks, professor emeritus of rhetoric at Yale University and an eminent Faulkner scholar. ''I date Cowley's 'Portable Faulker' and Robert Penn Warren's review on 'The Portable Faulkner' as the things that really brought Faulker into prominence. After that very shortly came the Nobel prize'' for Faulkner.

In 1956, he published his 18-year correspondence with Faulkner. In 1967, he produced a collection of his essays and reviews from the New Republic and other periodicals. He published a ''A Second Flowering: Works and Days of the Lost Generation,'' in 1973.

Cowley is survived by his wife, Muriel; one son, Robert, of New York; four grandchildren and two great-grandchildren. Funeral arrangements were not immediately available.