Line profiles were obtained from spectra of RR Lyrae taken with the 100” coudé with a dispersion of 10 A./mm, Profiles from two plates taken at maximum radial velocity and from two plates taken at minimum radial velocity were oppositely asymmetric as was predicted by the hypothesis of radial pulsation. A numerical measure of the change of the asymmetry was obtained which yielded Δa= +0·22 ± 0·017 for these profiles.