  The nature of fractional quantum Hall (FQH) states is determined by the
interplay between the Coulomb interaction and the symmetries of the system. The
unique combination of spin, valley, and orbital degeneracies in bilayer
graphene is predicted to produce novel and tunable FQH ground states. Here we
present local electronic compressibility measurements of the FQH effect in the
lowest Landau level of bilayer graphene. We observe incompressible FQH states
at filling factors v = 2p + 2/3 with hints of additional states appearing at v
= 2p + 3/5, where p = -2,-1, 0, and 1. This sequence of states breaks
particle-hole symmetry and instead obeys a v --> v + 2 symmetry, which
highlights the importance of the orbital degeneracy for many-body states in
bilayer graphene.
