  Subjet distributions were measured in neutral current deep inelastic ep
scattering with the ZEUS detector at HERA using an integrated luminosity of
81.7 pb-1. Jets were identified using the kT cluster algorithm in the
laboratory frame. Subjets were defined as jet-like substructures identified by
a reapplication of the cluster algorithm at a smaller value of the resolution
parameter ycut. Measurements of subjet distributions for jets with exactly two
subjets for ycut=0.05 are presented as functions of observables sensitive to
the pattern of parton radiation and to the colour coherence between the initial
and final states. Perturbative QCD predictions give an adequate description of
the data.
