Temperature–luminosity plots of the nongiant stars observed in Lupus 1, 3, and 4. Superimposed are selected evolutionary tracks of Baraffe et al. (1998) for stars above the substellar limit, merged with those of Chabrier et al. (2000) for brown dwarfs with dusty atmospheres. Objects with estimated log g ≃ 3.5 are marked as asterisks; those with log g ≃ 4.0, with crosses; and those with log g ≃ 4.5−5.0, with three-pointed stars.