  The production of hadrons in charged-current (anti)neutrino interactions is
studied with the bubble chamber BEBC exposed ot the CERN (anti)neutrino
wide-band beam. Fast-hadron production in a neon target is found to be
attennuated as compared to that in a hydrogen target. This feature is discussed
within the theoretical models based on the idea of a hadron formation length.
The experimental results favour the `constituent' over the `yo-yo' length
concept, and suggest a quark cross-section in the order of 3mb.
