The county board shall meet at such times and in such manner as provided by law. Each supervisor shall have special charge of the expenditure of money appropriated out of the county treasury by the board for roads, bridges, and culverts within his district, except in city districts when the board shall direct as to which one of the supervisors shall supervise the expenditure of the money appropriated as aforesaid. Said money so appropriated shall not include any money paid as automobile or motor vehicle registration or license fees and shall not be distributed by said board to the individual members thereof to be by them personally paid out upon their own private account nor in any manner whatever; but shall remain in the county treasury until a claim or claims for labor performed shall be properly verified, approved by said supervisor, filed with the county clerk, allowed by the county board, and a warrant drawn therefor.