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The 5.2 hr X-ray binary 4U 2129+47 was observed for a full orbital cycle using the imaging proportional counter detector and the monitor proportional counter detector aboard the Einstein Observatory, as well as a 0.9 m reflector for 5 hrs continuous optical photometry. The X-ray and optical light curves, the X-ray spectrum, and the times of optical and X-ray minimum were determined. The shape of the 5.2 hr X-ray light curve is independent of energy. A partial X-ray eclipse occurred which was centered on the time of optical minimum and which lasted 20 percent of the orbital period. During this interval the X-ray intensity varied smoothly by a factor of three, and the light curve was symmetric relative to the time of minimum. These findings argue that the X-ray emitting region is extended and highly ionized. A model is presented in which an accretion disk corona scatters radiation from a central accreting neutron star.

The Perek-Kohoutek planetary-nebula catalogue was searched for coincidences with the Kukarkin et al. variable-star catalogue. Twenty-six objects appear in both catalogues, but only one, the eclipsing binarv UU Sge, appears to be a genuine new variable planetary-nebula central star. The majority of the coincidences are with late-type variable stars erroneously listed as planetary nebulae. Key words: eclipsing binaries - planetary nebulae - symbiotic variables - variable stars

Slit spectrograms have been obtained and classified for 84 little-studied blue variable stars at high galactic latitudes. Several of the objects are newly recognized nova-like or RR Lyrae-type variables, and one is a symbiotic variable.

The historical light curve of the nova-like variable CD - 42 14462 = V3885 Sgr has been determined on 270 plates from the archival collection at Harvard. The object has remained at about B = 10.3, with random excursions of a few tenths of a magnitude up or down, since 1899. The bulk of the observational evidence supports the conclusion that CD -42 14462 is a dwarf nova in a state of permanent outburst. Key words: dwarf novae-close binaries-variable stars