Mr. Donald B. Benson, formerly of Watertown, died Sunday October 3, 2004 in the Elizabeth Seton Residence, Wellesley. He was 78. Born in Arlington, he was the son of the late Oscar B. and Esther F. (Larson) Benson. Donald is survived by his sister, Dorothy B. Farrell and her husband Dr. David Farrell of Weston and Chatham; one niece, Dorothy F. Shelton of Wayland; three nephews, David J. Farrell, Jr. of Chatham, James D. Farrell of Wayland, and John B. Farrell of Mansfield; and eight grandnieces and grandnephews. A Funeral Mass will be offered Wednesday at 10 a.m. in Saint Julia's Church, 374 Boston Post Road, Weston. Burial will be private. Visitation will be held prior to the Mass in The Joyce Funeral Home, 245 Main Street (Rte.20), Waltham from 8:30 to 9:30 a.m. Wednesday morning. In lieu of flowers, donations may be made to the Sisters of Charity, Elizabeth Seton Residence, 125 Oakland Street, Wellesley Hills, MA 02181.