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We report 17 new timings of primary eclipse minimum for the dwarf nova, U Gem. The orbital period of the binary system appears quasi-periodic. Possible causes of the ephemeris variability include nonconservative mass transfer, nonconservation of orbital angular momentum, relative motion of the hot spot within the system, apsidal motion, and a third star.

We have conducted a high-speed photometric study of the cataclysmic variable, LX Ser (a 1950 = 15 h 35 m 44 s ; ô 1950 = 19°01 , 30 ,/ , m v = 14), using the Cloudcroft 48-inch (1.2-m) synoptic telescope. We derive an orbital period of 0.15843194 (3 h 48 m 8?51 ± 0?1) at a zero epoch of HJD2444293.0240 ± 0.0003. The shapes of the eclipse light curves indicate that the hot-spot surface brightness morphology changes on a time scale of days and can be quite nonuniform, perhaps even irregular. Power-spectrum analysis of these data reveals only one instance (out of 16) of marginal evidence for periodic oscillations at ~ 0.007 Hz (~ 140 sec period).

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Relatively little is known about superclusters. Observations of superclusters should increase our understanding of these grandest aggregates of matter and may tell us a great deal about the large scale distribution of matter in the Universe. We report here observations of two superclusters chosen from the list by Murray et al. (1978, Ap. J. [Letters], 219, L89).