§ 42. Limitation on expenditures. The several amounts appropriated in any act shall be deemed to be only for so much thereof as shall be sufficient to accomplish in full the purposes designated by the appropriations and shall be paid by the division of the treasury, department of taxation and finance, from the respective funds as specified, pursuant to the requirements of this chapter. It shall be the duty of the comptroller to report annually to the legislature the detail of the several expenditures.