Section 12. Any such company neglecting to make the annual return required by the preceding section shall, for the first fifteen days or portion thereof during which such neglect continues, forfeit five dollars a day; for the second fifteen days or any portion thereof, ten dollars a day; and for each day thereafter a sum not exceeding fifteen dollars a day. If any company unreasonably refuses or neglects to make such return, it shall, in addition thereto, forfeit not more than five hundred dollars for each offence. All forfeitures recovered under this section shall be paid to the commonwealth.