The Spectrum of Chi Cygni Near Minimum Light.

Long-exposure spectrograms chiefly by I. S. Bowen with the 200-inch telescope show the extraordinary behavior of the rich bright-line spectrum of the long-period variable x Cygni near minimum light. Of 60 bright lines whose intensities increase markedly during the two months preceding minimum, one-third are forbidden lines of Fe II, two-thirds are unidentified. Differences in radial velocity between various groups of lines and between plates at various phases are small. A few suggestions for future observations are included.