Jakubiková Studenovská [4], has described all varieties of mono-unary algebras by identities. In the paper, we characterize all algebras in the variety generated by each irreducible unary algebra and show that for a positive integer nand nonnegative integer k, varieties of the forms  and  in Jakubiková Studenovská [4] are generated by a cycle and a loop with non-branched tail, respectively.

unary algebra, cycle, a loop with non-branched tail, irreducible algebra, identities, variety.