Theory predicts a rich mode spectrum for the dynamic excitations in antidot arrays. In addition to the dominating high ω1,0+- and low ωEMP+-modes, there are higher frequency ωn,m+- and in particular ωn,m−-modes with pillow-shaped anticyclotron motions in a magnetic field B. We have prepared antidot arrays with different potentials and were able to detect these modes.