“ The Commission concluded that persons and localities in interstate commerce, and interstate commerce, were being unduly discriminated against. Pursuant to s 13 (4) of the Interstate Commerce Act, 49 U.S.C. s 13 (4) , 49 U.S.C.A. s 13 (4) , it ordered intrastate fares raised to the level of interstate fares to remove the discrimination. A three-judge district court affirmed the order of the Commission as to the finding of discrimination against interstate commerce, but did not pass on the finding of discrimination against persons and localities in interstate commerce. ”