Section 19. No fees for the service of any process of which the officer is required to make a return shall be allowed, unless itemized and endorsed on the process; and no allowance for the use of a conveyance in the service of a civil process shall be made, unless the officer certifies that it was necessary for him to use a conveyance, and that he actually used such conveyance for the distance set forth in his certificate. An officer who makes a false certificate under this section or section ten shall forfeit thirty dollars for each offence, to the use of the commonwealth.