Two previously unreported emission lines at 6667.4 A and 6701.3 A have been detected and measured in the spectra of seven O and Of supergiant stars. While the line strengths are uncorrelated with the emission strengths of the N III multiplet 4634 A, 4640 A, 4641 A, or He II 4686 A, the correlation with the strength of the unidentified emission lines at 4486 A and 4504 A is excellent and very good with the C III 5696 A emission line. (Stellar emission measurements are relative to the continuum with no correction for any underlying stellar absorption.) The latter two results suggest that both pairs of unidentified lines arise from the same species which is probably related to C III as first suggested by Conti (1971).