that their rejection does not appear justifiable. Their effect on the mean life is large, of course. The ratio of the decay rates of H° and E" reported in this work is 0. 5ltg;g. The I A/1 = £ rule predicts i for this ratio. Other recently reported values of the E° mean life are (3. 8*J;°) xlO" 10 sec by Jauneau et al. 7 and (2. 5tS:J)xl0 Ll0 sec by Hubbard et al. 2