Section 84. Each such gas or electric company or manufacturing company or person 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 not more than fifteen dollars a day. If any such company or person unreasonably refuses or neglects to make such return, it or he shall, in addition thereto, forfeit not more than five hundred dollars. If a return is defective or appears to be erroneous, the department shall notify the company or person to amend it within fifteen days. A company or person neglecting to amend said return within the time specified in the notice, when notified to do so, shall forfeit fifteen dollars for each day during which such neglect continues. All forfeitures incurred under this section may be recovered by an information in equity brought in the supreme judicial court by the attorney general, at the relation of the department, and when so recovered shall be paid to the commonwealth.