  SU(3), baryon octets and a meson cloud model are compared for the flavor
asymmetry of sea quarks in the $\Sigma^+$, as an example. Large differences are
found, especially between SU(3) and the meson cloud model. We suggest Drell-Yan
measurements of $\Sigma^{+}-p$ and $\Sigma^{+}- d$ to test the prediction of
various models. We use the meson cloud model to predict both valence and sea
quark distributions.
