  An exotic meson, the $\pi_1(1400)$ with $J^{PC}=1^{-+}$, has been seen to
decay into a p-wave $\eta\pi$ system. If this decay conserves flavor SU(3),
then it can be shown that this exotic meson must be a four-quark state ($q\bar
q+q\bar q$) belonging to a flavor ${\bf10}\oplus{\bf\bar{10}}$ representation
of SU(3). In contrast, the $\pi_1(1600)$ with a substantial decay mode into
$\eta'\pi$ is likely to be a member of a flavor octet.
