  Data obtained by the Extreme Ultraviolet Explorer satellite are used to
determine the EUV spectrum of the quasi-coherent oscillations of the dwarf nova
SS Cygni. It is found that the spectrum of the oscillations is neither blue nor
red nor grey relative to the net (oscillation-phase integrated) spectrum, and
hence that the oscillations cannot be explained by variations in the effective
temperature, absorbing column density, or effective area, respectively.
Instead, it is found that the amplitude of the oscillations is high at the
relative maxima of the net spectrum, and low to zero at the relative minima of
the net spectrum. This behavior can be explained by either variations in the
emission line flux atop a constant underlying continuum, or variations in the
optical depth of a haze of overlapping absorption lines, in which case the
optical depths must be $\tau<1$ at the relative maxima of the net spectrum, and
$\tau\gg 1$ at the relative minima.
