Bianchi Type-I Cosmological Models with Variable G and 4Λ$-Terms in General Relativity

Einstein's field equations with variable gravitational and cosmological ``constant'' are considered in presence of perfect fluid for Bianchi type-I spacetime. Consequences of the four cases of the phenomenological decay of $Λ$ have been discussed which are consistent with observations. The physical significance of the cosmological models have also been discussed.