Diffuse interstellar bands in low color excess stars. III

Measurements of the equivalent widths of the diffuse interstellar bands at 6284 A and 6613 A in the spectra of 23 stars with E(B-V) less than 0.1 mag are reported. The band strengths do not correlate with interstellar H2 column density. They are probably produced by molecular mantles on grains or very stable molecules such as the polycyclic aromatic hydrocarbons.