  We combine optical (HST) and UV (GALEX) imaging of two intermediate redshift
galaxy clusters with spectroscopy of member galaxies, to study the relation
between the formation history of cluster galaxies and the assembly history of
the cluster structure itself. We identify key differences in the large-scale
structure and intracluster medium properties of each cluster. In order to
assess the importance of cluster substructure and the ICM in the evolution of
cluster galaxies, we examine several key indicators of the recent
star-formation and assembly history of cluster galaxies. We find that galaxies
in cluster MS0451 (z=0.54) exhibit a markedly lower incidence of recent star
formation activity than galaxies in cluster Cl0024 (z=0.39), likely the result
of starvation by the ICM. In addition, Cl0024 members show evidence for
kinematic disturbances that can be linked to the assembly of substructure.
