No person shall be permitted to be a director in more than one bank serving the same incorporated town or city doing business in this state. Any person holding a directorship in violation of this section shall be guilty of a misdemeanor, and upon conviction shall be fined not more than $100.00 and be ineligible to hold a directorship in any state bank within two years therefrom. This section shall not apply to savings banks and trust companies operated in connection with commercial banks doing business in the same building.