On a lonely lane winding amid stands of pecan trees and through fields of greening winter oats near Baton Rouge, a road construction gang one morning last week discovered the body of a woman: beside her 1960 Renault Dauphine lay Dr. Margaret Rosamond McMillan, 38, bludgeoned to death. The crime shook the campuses of Louisiana State University, both in Baton Rouge and at the New Orleans branch, where "Rosie" McMillan was an assistant professor of biology. The events that followed shook L.S.U. even harder.
A quiet, buxom spinster who shared her New Orleans house with a pair of cats, Biologist McMillan...