IN THIS ISSUE: A Solar Cell Based on a Biological System /2 (A pigment produced by bacteria may have commercial usefulness in solar cells that could convert water to hydrogen and oxygen. Early experimental work is described by Aaron Lewis, associate professor of applied and engineering physics.) ... Fuel Cells: A Clean, Efficient Source of Electricity /11 (Cells suitable for use in power plants can convert fossil fuels to electricity without combustion. The technology is discussed by Joseph F. Cocchetto, assistant professor of chemical engineering, who is conducting research on fuel cells.) ... Commentary: The Dean's State-of-the-CoIIege Report /20 ... Facets /26 (Professor Leonard Dworsky's leisure activities "under the water, up in the air" are featured in an article by the Quarterly's associate editor.) ... Faculty Publications /30 ... Letters /35 ... Editorial /36