We compared the multiplicities of pi (0), eta, K-0 and of charged particles
in quark and gluon jets in 3-jet events, as measured by the OPAL experimen
t at LEP. The comparisons were performed for distributions unfolded to 100%
pure quark and gluon jets, at an effective scale Q(jet) which took into ac
count topological dependences of the 3-jet environment. The ratio of partic
le multiplicity in gluon jets to that in quark jets as a function of Q(jet)
for pi (0), eta or K-0 was found to be independent of the particle species
. This is consistent with the QCD prediction that tile observed enhancement
in the mean particle rate in gluon jets with respect to quark jets should
be independent of particle species. In contrast to some theoretical predict
ions and previous observations, we observed no evidence for an enhancement
of eta meson production in gluon jets with respect to quark jets, beyond th
at observed for charged particles. We measured the ratio of the slope of th
e average charged particle multiplicity in gluon jets to that in quark jets
, C, and we compared it to a next-to-next-to-next-to leading order calculat
ion. Our result, C = 2.27 +/- 0.20(stat. + syst.), is about one standard de
viation higher than tile perturbative prediction.