Ethel M. Blacka of 200 Perry Ave.;Belle Vernon;died Tuesday;Oct.29;1985;at 8 p.m.in the Westmoreland Hospital;Greensburg. She was 74. Mrs.Blacka was born July 8;1911;a daughter of the late Ernest and Anna Yardley Barnes. She was a member of Marion Presbyterian Church;Fairhope;and the Missionary Society and Bethany Bible Class Aid of the church. A lifelong resident of the Fairhope area;Mrs.Blacka was a member of the Ladies Auxiliary of the Washington Township Volunteer Fire Department. A Girl Scout leader for many years;she was an avid camper at Scottyland in Somerset. Survivors include her husband;Charles F.Blacka Sr.;two sons;Charles F.Blacka Jr.of Carroll Township and Edward E.Blacka Sr.of Plum Borough;one daughter;Mrs.James R.(Gail) Koslosky of Carroll Township;one brother;Harry Barnes of Camp Hill;one sister;Lorena Martin of Westview;six grandchildren and two great-grandchildren. Friends will be received Wednesday from 7 to 9 p.m. and Thursday from 2 to 4 and 7 to 9 p.m. in the Shelby D.Ferguson Funeral Home;700 Broad Ave.;Belle Vernon;where services will be held Friday;Nov.1;1985 at 11 a.m. with the Rev.Mary Howard;pastor of Marion Presbyterian Church of Fairhope;officiating. Burial will be in Belle Vernon Cemetery. Shelby D.Ferguson;funeral director;is in charge of arrangements.