The variables investigated include ten stars of type Me and three of type Se (see Table I). Numerous spectrograms are listed in Table II. Intensities of bright lines.-Estimated intensities of H~, Thy, Hj3, Fe 4202, Fe 4308, and Mg 4571 served for the study of the behavior of these lines during the light-cycle. The relative intensities of pairs of lines rather than the intensities of individual lines were employed, thus avoiding serious photometric difficulties. The intensity ratio Hy: H~ in Me stars varies with phase in a striking manner. Typical behavior is as fol- lows: At one-fifth of the period before maximum, phase -0.2, the ratio is i/8; it rises rapidly to 1/2 at -0.05, then remains nearly constant until +0.2, after which it again rises rapidly to 2~ at about +0.4. In Se spectra the ratio has a minimum of 2~ at phase +0.07, with higher values earlier and later. The intensity ratio Hj3: Hy is not well de- fined in Me stars because Hf3 is seldom observed, and its intensity seems to vary in different cycles. In general, Hf3 grows relatively stronger after maximum. In Se spectra Hj3 is very intense. The ratio to Hy is high at early and late phases, with a minimum after maximum light. The intensity ratio X 4308: X 4202 behaves as follows in Me spec- tra: It is about 1/4 at phase +0.2, and increases steadily to i at +0.3 and 4 at +0.55. In type Se, X 4308 is 2~ times as intense as X 4202 whenever both are visible. In Me spectra the intensity ratio X 457 i: X 4308 has the following typical values: 2/3 at phase +0.15, I at +0.30, and 3 at +o.6. Wave-lengths and identifications of lines.-The mean wave-lengths of ftfty-eight bright lines are recorded in Table VIII. Most of these are true emission lines although a few may be maxima in the absorption spectrum. The elements identified include H, Fe i, Fe ii (both allowed and forbidden lines), Mg i, Si i, Mn i, Sr II?, In i? The for- bidden iron lines and an ultra-violet magnesium triplet have not previously been record- ed in these spectra. Data on individual stars, including wave-length measurements and the phases at which certain lines appear, are given in Tables V, VI, and VII and in the notes to Table VIII. D'isplacements of bright lines-The apparent velocities from the blue-violet lines are given in Table II. Plots showing the variation with phase are given for eleven stars in Figs. i6, i~, and i8. Algebraically decreasing velocity at and shortly after light- maximum, and a flat minimum 30-80 days after light-maximum are typical features.