  The feature of the low-lying spectrum and a complete set of quantum numbers
of the (e+e+e-e-) system have been deduced based on symmetry consideration. The
existence of a low odd-parity L=1 excited state with the spins of the two
electrons coupled to s1=1 and the two positrons coupled to s2=0 (or s1=0 and
s2=1) and a low even-parity L=0 excited state with s1=s2=1 have been predicted.
The discussion is generalized to 2-dimensional (e+e+e-e-) systems.
