In this paper, we report on observations of CH+ and other species accessible in optical wavelengths in the line of sight to HD 190603, a B1.5 lae supergiant. In this line of sight we see a shift in radial velocity between the CH+ line and other interstellar absorption lines such as CH and Ca I. The most likely explanation for this effect is the shock formation of CH+. We also make some estimates of likely preshock and postshock conditions which are consistent with the observations.

Spectra of several stars thought to be embedded in circumstellar dust shells are examined and evidence for circumstellar difflise band absorption is sought. Most of the objects are thought to be undergoing pre -main -sequence contraction, although a few are probably evolved objects undergoing mass loss. No evidence for circumstellar diffuse band formation is found in spite of the presence of substantial circumstellar extincti in some cases. Key words: circumstellar shells - difflise absorption bands - infrared excesses