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High resolution electronic absorption and fluorescence spectra of 1, 4-diphenylbutadiene, 1, 6-diphenylhexatriene and stilbene have been obtained in alkane Shpol’skii solvents and in 1, 2-diphenylethane crystals at 1.8$\circ K$, The well-resolved absorption and fluorescence spectra of 1, 4-diphenylbutadiene indicate that the first excited state is of $Bu$ symmetry. The first and second excited states of 1, 6-diphenylhexatriene are of $Ag$ and $Bu$ symmetry, respectively. High resolution studies of stilbene in 1,2-diphenylethane crystals show previously unresolved structure in the transitions of isolated molecules and of apparent aggregates of two or more stilbene molecules.