“ Although the record is not free from ambiguity, we take the Court of Appeals to have based its decision on the ground that the petitioner's amortization claims derived solely from net operating loss deductions carried forward from prior years, and that no additional amortization deductions for 1956 and 1957 were sought. Since we find that the petitioner adequately presented its amortization claims for 1956 and 1957, we vacate the judgment of the Court of Appeals and remand the case to that court for the consideration of those claims, without intimation of any kind as to their merit. ”