Isabel Washington Powell, a vibrant and familiar figure in the Oak Bluffs African American summer colony that traces its origins to the early twentieth century, died Tuesday at her home in Harlem, N.Y. She was 98.

Mrs. Powell, who was married to the late Cong. Adam Clayton Powell Jr. from 1933 until 1945, had owned a home in the Highlands section of Oak Bluffs since 1937, just down the street from the home of Dorothy West, the black writer and last surviving member of the Harlem Renaissance. The Powell home, nicknamed the Bunny Cottage, is now a landmark on the African American Heritage Trail of Martha's Vineyard.

"To be alive and be a part of this world, you have to be able to handle everything. You've got to know who you are in order to have a good life," she told the Vineyard Gazette in an interview seven years ago.

"Unquenchable vitality... has been characteristic of her life," wrote Robert C. Hayden in the second edition of his book African Americans on Martha's Vineyard.

Isabel Geraldine Washington was born May 23, 1908, in Savannah, Ga. Raised in Savannah, she lived with her parents, four brothers and four sisters.

In her early years, she moved to New York city to live with her sister Freddie Washington. Known as Belle, she followed Freddie into a career of show business, meeting future Cong. Adam Clayton Powell Jr. while dancing at the Cotton Club. They married in 1933 and were divorced in 1945.

The Powells spent their honeymoon on the Vineyard, where Mr. Powell had vacationed as a child with his father at the Shearer Cottage. In 1937 they bought their house on Vineland avenue, today renamed Dorothy West avenue. The Rev. Mr. Powell was pastor at the Abyssinian Church in Harlem, where his father had been the pastor. In 1944 he was elected to the U.S. Congress, the first black congressman from the eastern seaboard since after the Civil War. Mr. Powell died in 1972.

The Powells christened their house the Bunny Cottage after their nicknames for each other: Bunny Girl and Bunny Boy. Two white wooden rabbits stood guard on either side of the front door.

After her divorce, Mrs. Powell went on to a satisfying and challenging career in the Harlem public school system, working with young children. When she retired, she split her time between her home in Harlem and her cottage on the Vineyard.

Mrs. Powell spent every summer at the Bunny Cottage, where she tended flower beds and entertained a wide collection of guests on the front porch. An avid angler, she loved saltwater fishing and kept her ex-husband's fishing poles mounted on one wall of the cottage. "I haven't changed one thing in this house since Adam and I were divorced - not one thing!" she told Mr. Hayden in a 1998 interview for his book.

Mr. Hayden also writes about a wall-mounted flower bowl that was a gift from Matthew Henson, an African American who helped discover the North Pole in 1909. Mrs. Powell kept fresh flowers in the bowl throughout every summer.

Elegant and vivacious well into her ninth decade, in the 2000 Gazette interview she confessed that even at age 92 she never came downstairs without her makeup on. "Because I have to look at me. I know who I am. I know who I want to be, who until I die, I will always be," she said.

She is survived by her son Preston Powell, two grandchildren and five great-grandchildren.

A memorial celebration and tribute will be held Saturday, May 12 from 10 a.m. to noon at the Abyssinian Baptist Church in Harlem.