Spectral sequence of giants between B0 and B1, illustrating the progressive disappearance of the He II lines and the smooth inversion of the Si III/SI IV ratios. Lines used in classification criteria are shown on the top and bottom spectrum. Other metallic lines (after Kilian et al. 1991) are indicated on the middle spectra. See Fig. 3 for more line identifications and compare to Fig. A.2, where a sequence at much higher luminosity over the same spectral range is shown.