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Anisole (methoxybenzene) and styrene (vinylbenzene) are similar chemical species. However, their electronic strucures are very different. In this report, we describe the rotationally resolved fluorescence excitation spectra of the $S1\leftarrow Su$ origin bands of anisole and styrene. Both spectra are similar in overall appearance. However, a detailed analysis of the two spectra shows that the $S1\leftarrow S0$ optical transition moments have quite different orientations in the respective molecular frames. The results will be interpreted in the framework of a state-mixing model for the $S1$ states of the two molecules.