These cases, which were argued together, present the same questions. In each case, the taxpayer seeks to recover with interest an amount assessed and collected, after March 15, 1925, as an additional income and excess-profits tax for 1918 under the Revenue Act of 1918 (40 Stat. 1057). In each, the claim is that both the assessment and the collection were made after the expiration of the time allowed therefor. In a long line of cases arising out of similar facts, the Board of Tax Appeals has held consistently that neither the assessment nor the collection was made too late. In No. 414 the action was brought in the federal court for Massachusetts against the collector to recover $39,043.99. The District Court, without passing on the timeliness of the assessment, held that the collection was barred and entered judgment for the plaintiff, 28 F.(2d) 54. The Circuit Court of Appeals for the First Circuit affirmed the judgment on the ground that the assessment was barred, and expressed no opinion on the question decided by the District Court, 33 F.(2d) 739. In No. 118, the action was brought in the federal court for western Louisiana against the United States to recover $11,282.15. That court, deciding both questions in favor of the Government, entered a judgment for the defendant, 26 F.(2d) 505, which was affirmed, on both grounds, by the Circuit Court of Appeals for the Fifth Circuit, 29 F.(2d) 895. In other federal courts, also, there has been diversity of opinion. This court granted writs of certiorari, 280 U.S. 539, 50 S.C.t. 17, 74 L. Ed. -.
First. Whether the assessment was barred depends upon whether the period of limitation was started by the filing before March 15, 1919, of a so-called 'tentative return,' or by the later filing of a so-called 'completed return.' The question arises in this way: The Revenue Act of 1918 was not approved until February 24, 1919, c. 18, 40 Stat. 1057. Section 241(a) required that returns on the basis of the calendar year should be made on or before the 15th day of March. Section 239 required that a corporation's return should state 'specifically the items of its gross income and the deductions and credits allowed.' The form of return prescribed by the Commissioner of Internal Revenue for giving this information, known as Form 1120, is an elaborate document composed of a 'summary' in four schedules, with eleven supporting schedules and twenty-six subschedules. The 'summary' calls for the specification of some 93 items. The supporting schedules and subschedules call for the specification of some 357 items; and of as many more items to be stated in appendices as the circumstances of the particular taxpayers might require.