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Image-tube spectrograms (resolution 1 A) of the Ha emission line in 15 late-type dwarf stars are examined for evidence of equivalent-width variability on a time scale of days, weeks, and years. Scattered data show Ha variations in three known BY Draconis variables: YY Gem, Gl 182, and BD +48" 1958A. A much more extensive series of spectrograms of BY I)ra itself obtained during 1972 and 1976 shows only a marginal correlation between Ha EW and rotational phase. Criteria for detection of such variability are noted.
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Bopp et al. (1978) studied this question.
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