We discuss the decays X* -> Xe+ e(-) ("Dalitz decays") of excited heavy mes
ons into their ground states and an electron-positron pair. We argue that t
he measurement of the invariant mass spectrum of the lepton pair gives clea
r indication on the quantum numbers of the excited meson and thus provides
an experimental test of the quark model predictions. (C) 2000 Elsevier Scie
nce E.V. All rights reserved.