  Flavor asymmetries for the valence and sea quarks of the $\Sigma^{\pm}$ can
be obtained from Drell-Yan experiments using charged hyperon beams on proton
and deuteron targets. A large, measurable difference in sea quark asymmetries
is predicted between SU(3) and pseudoscalar meson models. The latter predict
that in $\Sigma^{+}$, $\bar{u}/\bar{d} \leq 1/2$, whereas the former predict
$\bar{u}/\bar{d} \approx 4/3$. Estimates of valence quark asymmetries based on
quark models also show large deviations from SU(3) predictions, which should be
measurable.
