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The pyrazine molecules serves as a prototype of an intermediate case molecule in the theory of intramolecular radiationless transitions. The main attention is focused on the fluorescence decay of the first excited singlet $(1B3u)$ electronic state. For a recent review see [1] and the references therein. The high resolution absorption spectrum of the P, Q and R. branches of the 0-0 electronic transition of pyrazine was recorded with a bolometer in a supersonic molecular beam and a single mode, frequency doubled ring dye laser. A residual Doppler linewidth of 50 MHz was achieved. Simultaneously with the absorption spectrum the laser induced fluorescence spectrum was observed A comparison is made between excitation and absorption inensities of the molecular eigenstate spectra. It is concluded that substantial differences exist between both spectra.