With a new type of high-pressure cell the angular dependence of light scattering intensities at scattering angles B between 30" and 150" can be measured as a function of pressure P . The linear extrapolation of (v)-I as a function of sin2 (8/2) to B = 0 does not show an angular dependence of the scattering intensities. For this result the term including sin' (8/2) in Debye's equation for the critical opalescence vanishes. The reason for_this is probably due to the low molar mass of the polystyrene (number-average molar mass M, = 1 OOO g h o l ) . This means that the range of molecular forces of a polymer/solvent system is too small to be detected by light scattering. A second linear extrapolation of (r)-I to B = 0 as a function of P yields th: spinodal points of the system polystyrene/pentane in the temperature-pressure-concentration diagram.