Relations are presently established among T(eff), colors, and metallicity for a sample of Population I and II F and G main-sequence stars whose physical parameters and photometric indices are well known. A comparison of these results with empirical calibrations, as well as the Yale and vandenBergh and Bell (1985) colors shows that theoretical

High-resolution spectra provide evidence of the Li-I 6707 line in 28 of the stars, and the significance of the results is discussed. The Li-I equivalent widths are presented after correcting for continuum veiling with actual measurements of the veiling itself. Surface spots are found to have a complex effect on the width of the photospheric lines

Photopolarimetric observations in UBVRI bands and near-infrared photometric observations of the low polarization quasar 3C 273 obtained between February 1989 and May 1990 are presented. The degree of polarization remained low (below 1 percent) for most of the observing period and generally decreased toward shorter wavelengths. In early 1990

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Emission lines in the spectra of WC9 stars have been studied. It is shown that there are clear differences between the spectra of BD + 30 3639 and the central star of He2-99. It is argued that there are no systematic spectral differences between the WC9 CSPN and the Pop.I WC9 stars: both kinds of WC9 stars show a substantial and overlapping range