Lithium abundances of intermediate-mass, pre-main-sequence stars in Orion IC

Li abundances in the premain sequence cluster Orion Ic are estimated. Six stars out of the sample of 23 appear to show Li depletions. The mean Li abundance is log N (Li) = 3/6 +/- 0.1, a factor of two larger than the initial solar Li abundance. Differences at hotter temperature between the Orion abundances and those in the slightly older cluster Alpha Per cannot be explained by standard models or the new rotational Yale models. A possible explanation for the spread is that rotational braking has already occurred for some of the Orion Ic stars. The Li abundances of the six depleted stars are not inconsistent with the few Li abundances determined in main sequence stars of the same mass.