Completely regular semigroups S are taken here with the unary operation of inversion within the maximal subgroups of S. As such they form a variety CR whose lattice of subvarieties is denoted by L(CR). The relation on L(CR) which identifies two varieties if they contain the same bands is denoted by B<^>. The upper ends of B<^>-classes which are neither equal to CR nor contained in the variety CS of completely simple semigroups are generated by two countably infinite ascending chains called canonical varieties. In a previous publication, we constructed the sublattice Sigma of L(CR) generated by CS and the first four canonical varieties. Here we extend Sigma to the sublattice Psi of L(CR) generated by CS and the first six canonical varieties. For each of the varieties in Psi\Sigma, we construct the ladder and a basis of its identities.