  In the presence of independent generations of leptons, I show that the same
type of ambiguity in the mass spectrum arises as was discussed in ref.[1] for
neutral kaons. It results from the freedom to add to their Majorana mass
matrix, usually taken to be symmetric, an antisymmetric term which vanishes as
soon as fermions belonging to different generations anticommute. In the simple
examples proposed, dealing with two generations, this procedure introduces an
extra (mass) parameter $\rho$, which is shown to connect the (CP violating)
mixing angle to the hierarchy of neutrino masses. We use this opportunity to
investigate the relations between the two; in particular, large hierarchies are
no longer preferentially attached to small mixing angles; this can be relevant
for the ``Large Mixing Angle'' solution strongly advocated by recent
experiments on neutrinos oscillations. I discuss how the $\rho$ parameter could
be fixed, which appears, in the absence of a substructure for leptons, still
more delicate than for kaons.
