On the Spectrum of β Lyrae

The wave-lengths of 240 absorption lines in the spectrum of the B8 component of $ Lyrae are given. Of these, 176 are identified with H, He i, Ca ii, Si ii, Si iii, Cr ii, Sc ii, Ni ii, Mg ii, Fe i, Fe ii, Ti ii, Sr ii, S ii, N ii, and V ii. A comparison of this component of 13 Lyrae with the supergiants /3 Orionis (B8 p) and ~ Cygni (Aop) is made, with the result that the so-called B8 component is found to be normal for the later class of B9. The lines in the spectrum of the B5 component are compared with those in the spectrum of 67 Ophiuchi (B5) and, as many important B5 lines are missing, the con- clusion is reached that the B~ spectrum is not normal for its class. A plate with phase oc138, which showed exceptionally strong H and He emission, showed also additional emission lines not seen at other phases. These are identified with Nii 4621, N II 4630, Nii 4643, and Mg ii 4481