New transitions and levels in 148 Ce have been observed in a γ-γ-γ coincidence study from the spontaneous fission of 252 Cf with Gammasphere detector array. The ground band has been extended up to I π = 22 + , and side bands are extended with I = 2 stretched transitions and I = 1 crossing transitions. The observed level scheme is interpreted in terms of possible octupole correlations. Two sets of interwined positive-and negativeparity bands with the simplex quantum numbers s = ±1 are suggested. The results of B(E1)/B(E2) branching ratios indicate that the octupole correlations in 148 Ce are strong.

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High-spin states in the odd-odd 138 Pr nucleus were reinvestigated with the reaction 128 Te( 14 N, 4n) at a beam energy of 64 MeV. Six collective bands were observed, and two of them were newly identified. For the πh 11/2 ⊗ νh 11/2 band, high-spin states are followed up to I π = 16 + . The spin values for this band have been reassigned based on the systematical comparison with the neighboring nuclei. The observed band crossing is proposed to be due to the alignment of protons, and the signature inversion with the neutron number changing in La and Pr isotopes has been discussed. The other five collective bands are proposed to be based on oblate deformation with γ ∼ −60 • .