(a)in any Central Act passed after the [commencement] [Ist April, 1937.] of Part III of the Government of India Act, 1935, shall mean any part of His Majestys dominions exclusive of the British Islands, the Dominions of India and Pakistan (and before the [establishment] [15th August, 1947.] of those Dominions, British India), any Dominions as defined in the Statute of Westminster, 1931, any Province or State forming part of any of the said Dominions, and British Burma; and