No member bank shall act as the medium or agent of any nonbanking corporation, partnership, association, business trust, or individual in making loans on the security of stocks, bonds, and other investment securities to brokers or dealers in stocks, bonds, and other investment securities. Every violation of this provision by any member bank shall be punishable by a fine of not more than $100 per day during the continuance of such violation; and such fine may be collected, by suit or otherwise, by the Federal reserve bank of the district in which such member bank is located.