Cumulative yield isomeric ratios ( σ m / σ g ) c have been measured in the fission of 230Th, 232Th, and 236U by helium ions of various energies. The data show the ratio to increase with energy. The angular distribution of the 111Pd fission products indicates a maximum at 180° to the beam direction and a minimum at 90°. The isomeric ratio does not vary with angle within the accuracy of the experiment. Measurements of ( σ m / σ g ) c in the photofission of 232Th, 238U, 236U, 235U, 234U and 233U show a sharp increase with the fission parameter Z 2/A. Independent yield isomeric ratios have been calculated from the measured ratios by applying the results of various charge distribution studies reported in the literature. These calculated ratios suggest that there is little correlation between the initial angular momentum of the compound nucleus and the isomeric ratio of the fission product.