We have analyzed the properties of a sample of 33 groups and clusters of galaxies for which both optical and X-ray data were available in the literature. This sample was built to examine the baryon content and to check for trends over a decade in temperature down to 1keV. We examine the relative contribution of galaxies and ICM to baryons in clusters through the gas-to-stellar mass ratio (M_gas_/M_*_). We find that the typical stellar contribution to the baryonic mass is between 5 and 20%, at the virial radius. The ratio (M_gas_/M_*_) is found to be roughly independent of temperature. Therefore, we do not confirm the trend of increasing gas-to-stellar mass ratio with increasing temperature as previously claimed.