.The motion of the Solicitor General for an extension of time to file & brief - in these cases is granted and. the time is extended to and including April 15, 1959.' The plaintiffs are allowed to and including April 30,' 1959, to file their reply brief, to the answer of the defendants and to reply to the brief of the Solicitor' General, if so advised. Defendants are allowed to and including April 30, 1959, to reply to the brief of the Solicitor General, if so advised.