  The data from the last seven experiments performed on polarized
deep--inelastic scattering on proton and neutron (or deuteron) targets have
been analyzed in search of a precise determination of the spin fraction carried
by the quarks in the nucleon. We find that this fraction can be of the size
expected from na\"{\i}ve quark model arguments, provided the gluon axial
anomaly is explicitly included and the isosinglet axial charge normalization is
fixed at a suitably low momentum scale, such that a) the running, strong
coupling constant is about unit, and b) the orbital angular momentum inside the
nucleon vanishes.
  We also find that, despite the appeal of this solution of the ``nucleon spin
crisis'', a solution where the axial anomaly is absent and its effects are
traded for an appreciable strange quark polarization can not however be
excluded --- because of the limited accuracy of the data --- unless this latter
and/or the gluon polarization in the nucleon are explicitly measured.
