One of the largest picnics in the nation will take place Saturday, April 16, when tens of thousands of people come to the University of California, Davis, for its annual Picnic Day. Opening ceremonies for the daylong 81st campus open house will begin at 9:30 a.m. on the north end of the Quad, followed by a traditional parade through the campus and downtown Davis. The parade marshals will be Thomas B. Dutton, retired vice chancellor of student affairs, and Darby Morrisroe, this past year's student regent. Dutton served the campus for nearly 21 years as the vice chancellor before announcing his retirement in 1991. Morrisroe is a fifth-year senior majoring in political science and is former director of the State Lobby for the Associated Students of UC Davis. In addition to serving her one-year term as regent, she is taking 19 units of classes and is working as an academic peer adviser in political science to support herself financially. "Students Shining Through" is the theme of this year's celebration. UC Davis students chose the theme to reflect student achievement, according to Heather Marshall, Picnic Day publicity chair. Attached is a schedule of events. Highlights for the day include: • Chemistry magic show. 11:30 a.m. in 194 Chemistry Building • Police dog agility demonstrations and the traditional dachshund races are among several different dog events scheduled. 11 a.m. to 4 p.m. near Recreation Hall • Faculty mini-lectures. Noon to 3:30 p.m. in the Quad area • Soccer, tennis, volleyball, diving, rugby and karate will highlight a day of intercollegiate athletic competition and sporting exhibitions. 10 a.m. to 6 p.m. at all athletic fields and Hickey Gym Musical entertainment, department exhibits, a college bowl exhibition match and antique farm machinery displays are also planned. Food concessions will be available on campus, but no alcohol is allowed. This year's Picnic Day was organized by a 12-member student board of directors led by Erik Jarvi.