A memorial service for Dr. Lillian Milgram Schapiro, widow of Meyer Schapio, the Columbia art history professor, will be held Oct. 29 at Columbia University. Dr. Milgram Schapiro, who died Sept. 6 at her home in the Village at the age of 104, was under the 24-hour, seven-days care in recent years of two sisters, Iris and Norma Campbell, and their niece Annette Bonnick.