William C. Crossman Sr., 85, a lifelong resident of Virginia and owner and operator of one of Arlington County's last working dairy farms, died of pneumonia Thursday at Arlington Hospital.

Mr. Crossman lived for 61 years in the North Arlington home where he was born. As a young man, he helped his father run the family dairy farm, which was established in Arlington after the Civil War. He later managed the farm until his retirement in 1949.

From then until his second retirement about five years ago, he was superintendent of Oakwood Cemetery in Falls Church.

He was a member of Crossman United Methodist Church of Falls Church, which was founded by his grandfather, the late Isaac Crossman, in 1874.

He was a 60-year member of Kemper Lodge No. 64 of the Masons.

Survivors include his wife, the former Mary A. Holloman, of Arlington; a son, William C. Jr., of Hague, Va., a daughter, Virginia C. Groves of Arlington; a brother, George, of Hamilton, Va.; two sisters, Florence Taylor of McLean, and Louise Shaw of Pompano Beach, Fla., 10 grandchildren and seven great-grandchildren.

The family suggests that expressions of sympathy be in the form of contributions to Crossman United Methodist Church.