Relation of the gas mass inferred from the Schmidt law to the stellar population parameters. Top left: Histograms of the gas (blue) and stellar (red) masses, showing that the range in stellar mass is significantly broader than the range in gas mass. Top right: Gas mass vs. stellar mass. Gas masses are relatively constant across the sample, but when the galaxies with ﹩M_{\mathrm{dyn}\,}/ M_{\star }> 10﹩ are not considered we see an increase in gas mass with stellar mass. Bottom panels: The gas fraction strongly decreases with increasing stellar mass (left) and age (right). The solid line and accompanying shaded region in the bottom left panel show the minimum detectable gas fraction set by our Hα flux detection limit, for the mean (solid line) and range (shaded region) of sizes observed. Symbols are as in Fig. 7, and the error bars in the corner of each plot show typical uncertainties.