NGC 3311 , the central cD galaxy in the Hydra cluster , was previously thought to host the most metal–rich globular cluster system known .
Ground–based Washington photometry had indicated the almost complete absence of the population of globular clusters near [ Fe/H ] \sim - 1 dex , normally dominant in the metallicity distribution functions of giant elliptical galaxies .
Lacking the normal metal–poor globular cluster population , NGC 3311 was an outstanding exception among galaxies , not easily understood under any of the current globular cluster formation scenarios .
Our HST/WFPC2 data yield normal globular cluster colors and hence metallicities for this galaxy .
We find a bi–modal color distribution with peaks at ( V - I ) _ { o } = 0.91 \pm 0.03 and 1.09 \pm 0.03 , corresponding to [ Fe/H ] \sim - 1.5 and -0.75 dex ( somewhat dependent on the choice of the conversion relation between color and metallicity ) .
We review the evidence for exclusively metal–rich globular cluster systems in other galaxies and briefly discuss the implications for our understanding of globular cluster and galaxy formation .