The symmetries of the $t=1$ and $t=0$ pair-fields are different. The
consequences for rotational spectra are discussed. For $t=1$, the concept of
spontaneous breaking and subsequent restoration of the isospin symmetry turns
out to be important. It permits us to describe the proton-neutron
pair-correlation within the conventional frame of pairing between like
particles. The experimental data are consistent with the presence of a $t=1$
field at low spin in $N\approx Z$ nuclei. For a substantial $t=0$ field, the
spectra of even-even and odd-odd $N\approx Z$ nuclei become similar. The
possibility of a rotationally induced $ J=1$ pair-field at high spin is
considered.Comment: 7 pages 9 figure
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