CN-CH planes for our final data set, divided into 0.1-dex-wide bins in [Fe/H]. The CH bandstrength index S(CH) is plotted versus the CN bandstrength residual δS(3839), and candidate globular cluster stars are drawn as open circles. As in Fig. 3, the maximum metallicity in each bin is given in the upper left corner. As is explained in the text, we select as candidate globular cluster stars all those with relatively high δS(3839) in the three highest-metallicity bins, and stars with both high δS(3839) and S(CH) below the mean S(CH) of the CN-normal group in all other metallicity bins.