Upper panel: 10 μm peak-over-continuum distribution among the HAeBe stars (Juhász et al. 2010) in comparison with the IMTT star sample. Middle panel: 10 μm peak-over-continuum distribution among T Tauri stars (Furlan et al. 2011) in comparison with the intermediate-mass star samples (IMTTs+HAeBe). Because of the large difference in sample size, the distributions have been normalized so that their peak value equals 1. Lower panel: distribution in the F_11.3 /F_9.8 ratio clearlyshowing the separation between the large grain group and the smaller grain group among the IMTT stars, as well as the fact that Group 1 disks more commonly have smaller grains.