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We investigate the galaxy populations in seven X-ray selected,intermediate-redshift groups (0.2<z<0.6). Overall, the galaxy populations inthese systems are similar to those in clusters at the same redshift; they havelarge fractions of early-type galaxies (f_e~70%) and small fractions ofgalaxies with significant star formation (f_[OII]~30%). We do not observe astrong evolution in the galaxy populations from those seen in X-ray luminousgroups at low-redshift. Both f_e and f_[OII] are correlated with radius but donot reach the field value out to ~r_500. However, we find significant variationin the galaxy populations between groups with some groups having field-likepopulations. Comparisons between the morphological and spectral properties ofgroup galaxies reveal both gas-poor mergers and a population of passivespirals. Unlike low-redshift, X-ray emitting groups, in some of these groupsthe brightest galaxy does not lie at the center of the X-ray emission, and inseveral of the groups that do have a central BGG, the BGG has multiplecomponents. These groups appear to represent a range of evolutionary stages inthe formation of the BGG. Some groups have relatively large central galaxydensities, and one group contains a string of seven bright galaxies within aradius of 200 kpc that have a lower velocity dispersion than the rest of thesystem. None of the central galaxies, including those with multiple components,have significant [OII] emission. These observations support a scenario in whichBGGs are formed relatively late through gas-poor mergers.

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