  We study chiral symmetry aspects of the positive and negative parity baryons
by identifying them with linear representations of the chiral group $SU(N_{f})
\otimes SU(N_{f})$. It is shown that there are two distinctive schemes: naive
and mirror assignments. We construct linear sigma models for baryons in the two
assignments and examine their physical implications. Then we investigate
properties of the naive and mirror nucleons microscopically by using QCD
interpolating fields. Finally, we propose experiments to distinguish the two
chiral assignments for the nucleon.
