The continental United States, excluding Alaska, shall be divided into not less than eight nor more than twelve districts. Such districts may be readjusted and new districts may from time to time be created by the Board of Governors of the Federal Reserve System, not to exceed twelve in all: , That the districts shall be apportioned with due regard to the convenience and customary course of business and shall not necessarily be coterminous with any State or States. Such districts shall be known as Federal reserve districts and may be designated by number. When the State of Alaska or Hawaii is hereafter admitted to the Union the Federal Reserve districts shall be readjusted by the Board of Governors of the Federal Reserve System in such manner as to include such State. Every national bank in any State shall, upon commencing business or within ninety days after admission into the Union of the State in which it is located, become a member bank of the Federal Reserve System by subscribing and paying for stock in the Federal Reserve bank of its district in accordance with the provisions of this chapter and shall thereupon be an insured bank under the Federal Deposit Insurance Act [ et seq.], and failure to do so shall subject such bank to the penalty provided by .112 U.S.C. 1811section 501a of this titleProvided