Search for transit effects in spectra of 51 Pegasi and HD 209458

We have used high-resolution optical spectra to search for obvious absorpti on or emission lines from the planets orbiting HD 209458 and 51 Pegasi. For each star, two spectra were obtained during inferior conjunction, enabling the detection of absorption lines from the planetary atmosphere. Spectra w ere also examined at a full range of orbital phases. The search involved su btracting spectra during transit from reference spectra taken out of transi t. We found no significant variations in the spectra of HD 209458 and 51 Pe g at any orbital phase, with typical detection thresholds of several percen t. Velocity measurements of HD 209458 taken 40 minutes after midtransit fal l similar to 20 m s(-1) below the Keplerian Dt, presumably due to the plane t removing flux from the receding hemisphere of the rotating stellar surfac e. This is consistent with the planet orbiting in the same direction as the star spins, in agreement with recent work by D. Queloz and coworkers.