Classical and low-angle laser light-scattering experiments were performed to measure the second virial coefficient, A(2), and radius of gyration, R(g), of linear poly(alpha-methylstyrene) (P alpha MS) in the poor solvent cyclohexane. The molecular weights, M(w), of the polymers used cover the range of 60 000-3 500 000, and all samples have narrow molecular weight distributions. The experimental temperatures are controlled down to about 16 degrees C below the Theta temperature (36.2 degrees C). At this temperature, the scaling exponent of R(g) with M(w) is 0.414; this appears to be the lowest exponent ever reported for linear chains of synthetic polymers in solution. A strong molecular weight dependence of the measured A(2) values for this P alpha MS/cyclohexane system is observed. These results are compared with the predictions of available theories and with other experimental results.