Be Stars in Open Clusters.

141,183, 1965) listed slit spectral types for 25 members in XGC 6530 of type B3 and earlier and classified 18 as of type Be, but mentioned that their spectra may be contaminated by the strong Ha emission of M8. Three of the 18 stars are known Be stars; Xo. 58 is LkHa 112 (Herbig, Astrophys. J. 125, 654,1957), Xo. 65 is MWC 280, and Xo. 100 is Xo. 25, Table I, Tonantzintla-Tacubaya 13, 12. Four- and ten- degree Ha objective prism plates of XGC 6530 taken with the Curtis Schmidt-type telescope of The University of Michigan show the presence of em ission in the three known Be stars but fail to show it for the other stars. The objective prism method is preferable to the slit method for the discovery of Ha-emission stars in H II regions. Upon similar 100 plates three new Be stars were discovered in each of the clusters XGC 7654 and XG 2421; the number of Be stars in the former cluster is thus six. UB V photometry of the Be stars and brighter members of XGC 2421 was recently carried out at the Cerro Tololo Inter-American Observatory. A search program for Be stars in clusters containing B stars is described.