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Optical spectropolarimetry of the FUor Z CMa in 1991-1992 shows larger polarization in the emission lines than in the continuum. The intensity spectrum at this time has absorption lines with some narrow weak emission. The polarized flux spectrum appears similar to a previous intensity spectrum of Z CMa obtained when it was $\sim 0.9$ magnitudes brighter at $V$ and showed strong emission lines. We argue that the primary component of the Z CMa binary is an emission line source, perhaps an Ae/Be star, that has varied at $V$ by 1-3 magnitudes. The primary is mostly obscured from view by an asymmetrical distribution of dust which polarizes the light scattered into our line of sight. The secondary, a normal FUor, has a less obscured view, and therefore contributes a large amount of unpolarized flux, about 80\% of the total optical flux. We propose that variations in the brightness of the primary are responsible for the appearance and disappearance of a narrow emission line spectrum on the broader FUor absorption line spectrum.
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