Tony Williams, 51, who set the standard for modern jazz drumming as a teenage prodigy with the Miles Davis Quintet and later became a seminal figure in jazz-rock fusion, died Feb. 23 at a hospital in Daly City, Calif., where he was recovering from gall bladder surgery.

He was considered by musicians and critics alike one of the most inventive jazz drummers since the 1960s. He played with musicians as diverse as jazz legends John Coltrane and Thelonious Monk, rock superstars Jimi Hendrix and Bruce Springsteen and the avant-garde classical group the Kronos Quartet.

Miles Davis, who already had an established reputation in 1963, tapped the 17-year-old drummer to play in his group. "A drummer like Tony comes along only once in 30 years," Davis said.

Davis's group, which also included saxophonist Wayne Shorter, pianist Herbie Hancock and bassist Ron Carter, still is considered one of the greatest ever in jazz. A reunion album, "The Tribute to Miles Davis," with Wallace Roney on trumpet, was awarded a Grammy in 1995.

Mr. Williams, a resident of Pacifica, Calif., was born in Chicago and raised in Boston. He began playing drums at age 8 with his father, learning from musicians such as Art Blakey and Max Roach. By age 12, he was receiving private lessons from a teacher at the prestigious Berklee School of Music in Boston.

At age 14, Mr. Williams began to play professionally, but he got his big break in jazz in 1962, when he was asked to move to New York by the alto saxophonist Jackie McLean.

A year later, he joined the Miles Davis Quintet, and by age 18, Mr. Williams received a solo recording contract from Blue Note Records and released his debut album, "Lifetime" -- the first avant-garde project released by the mainstream jazz label and also considered one of the earliest jazz fusion albums.

Mr. Williams played with Davis, Hancock, Carter and Shorter until 1968 and collaborated on 13 albums. He grew restless with Davis's group and formed what many consider to be the first jazz-rock fusion group, Lifetime, with guitarist John McLaughlin and organist Larry Young. The group released the hugely innovative record, "Once in a Lifetime," on Verve.

But Mr. Williams, disillusioned by criticism of his retreat from pure jazz, stopped performing in 1972. He returned four years later to back Hancock's group, V.S.O.P.

After moving from New York to the San Francisco Bay area in the mid-1970s, Mr. Williams began studying classical composition at the University of California at Berkeley.

His manager, Greg DiGiovine, said Mr. Williams pioneered the use of melodies and counter-rhythm in percussion and incorporated blues, country and classical music into his style.

"He had accomplished so much and he changed the style of drumming so dramatically that everyone was hard-pressed to understand or catch up to him, even today," DiGiovine said.

"In the musicians' world, a lot of people come and go, and they end up being a footnote," he said. "But in the world of drums, Tony was a legend, and everybody knew it."

Mr. Williams recorded for Blue Note, Columbia Records, Polydor and most recently Ark 21 Records. His final release last year was "Wilderness," featuring guitarist Pat Metheny, saxophonist Michael Brecker, Hancock and bassist Stanley Clarke with a 30-piece orchestra.

Survivors include his wife, Colleen Williams, and his mother, Alyse Janez. ANN HOPPER BROWN Planning Commissioner

Ann Hopper Brown, 87, a park and recreation activist who had served five years on the Prince George's County Planning Board, died of congestive heart failure Feb. 22 at home in Fort Washington.

Mrs. Brown had lived in the Washington area since 1930. During the 1950s, she was a clerk with the Military Air Transport Service, and she had worked earlier for other federal agencies for a total of about 17 years of federal service.

From 1975 to 1980, she served on the Prince George's County Planning Board, and in that capacity, she was a member of the Maryland-National Capital Park and Planning Commission. In these roles, she was an advocate of parklands and balanced growth.

She was a member of the Oxon Hill Democratic Club, the Allentown Recreation Council and the Prince George's County Federation of Park and Recreation Councils. She had served on the Prince George's Recreation Advisory Board and the board of trustees of the National Recreation and Parks Association.

Mrs. Brown had worked for the establishment of the Tucker Road ice rink and the Cosca Regional Park and nature center.

As a young woman, she sang in the choir of St. Thomas Episcopal Church in Washington. She later was a founder of Bethel Free Methodist Church in Fort Washington Oaklawn Cemetery Association.

She was born in Bridger, Mont., and grew up in Binghamton, N.Y., and and Delta, Pa. During the 1920s, she sang popular and folk music on the radio in York, Pa.

Her first husband, John Hopper, died in 1981.

Survivors include her husband, Bennie H. Brown of Fort Washington; three children from her first marriage, John Craig Hopper of Calvert County, Ann Cosnka of Herndon and Catharine House of Sterling; six grandchildren; and four great-grandchildren. WILLIAM BLACKBURN BARTON Commerce Department Official

William Blackburn Barton, 97, who retired as general counsel of the Chamber of Commerce after nearly 20 years, died of complications after a fall Feb. 20 at his home in Boca Raton, Fla.

Mr. Barton, a Kansas native, was a graduate of Northwestern University and later received a law degree from Yale University. He practiced law in Los Angeles for 10 years before receiving a master's degree in corporate and business law from Columbia University.

In the late 1930s, he moved to Washington and became a trial examiner for the National Labor Relations Board. He then became the manager of the Labor Relations Department of the Chamber of Commerce, frequently giving congressional testimony and helping write the 1959 Landrum-Griffin Act, a cornerstone of modern labor law.

During that time, he also served as legal adviser for the U.S. management delegation to the annual International Labor Conference in Geneva. In the early 1950s, he became general counsel of the Chamber of Commerce, a position he held until his 1964 retirement.

After retiring, he continued to practice law in Washington until moving to Florida in 1995.

He taught Sunday school at Foundry United Methodist Church in Washington and served on the boards of Sibley Memorial Hospital and the Cosmos Club.

His first wife, Marian Humphreys, died in 1971.

Survivors include his wife, Dorothy Rindge of Boca Raton; two children from his first marriage, Sara Ellen Ringley of Columbia, S.C., and William Barton Jr. of Mclean; and a grandson.