“ On the Government's concession, which we accept, as to the charge of conspiracy to export gold and to commit counterfeiting offenses, the judgment of the Court of Appeals cannot be sustained. We do not consider the merits of the Government's contention that the conviction can be sustained on other grounds, since, in the circumstances of this case, we deem it more appropriate that the Court of Appeals consider that question in the first instance. ”

“ It admits that petitioner's story of his negotiations with Nazi agents was sham, as he testified at the trial, and as is shown by other evidence submitted to the jury and by the failure of the Government to produce evidence of contacts with Nazi agents although petitioner was under almost constant surveillance by government agents. The Government also concedes that it has no evidence and that there is none in the record to support petitioner's conviction on any theory of a conspiracy to export gold. ”

“ But the Government argues that there is evidence in the record sufficient to sustain the conviction of petitioner and Smith of conspiracy to acquire gold without the prescribed license, notwithstanding the Government's failure to seek a review of the reversal of Smith's conviction. ”