We discuss observables in multiparticle production for three kinds of limits
of decreasing kinematical scales: 1. the transition jet \to hadron (limit
y_{cut}\to 0 of the resolution parameter y_{cut}); 2. single particle inclusive
distributions normalized at threshold \sqrt s\to 0 and 3. particle densities in
the limit of low momentum p,p_T\to 0. The observables show a smooth behaviour
in these limits and follow the perturbative QCD predictions, originally
designed for large scales, whereby a simple prescription is supplemented to
take into account mass effects. A corresponding physical picture is described.Comment: talk at Ringberg workshop "New trends in HERA physics 1999",
Tegernsee, May 1999; LaTeX, 13 pages, 6 Fig
