72 Pa. Stat. § 3441
All moneys derived from registrations and from license fees, under the provisions of the act of Assembly, approved July seventh, one thousand nine hundred and thirteen, relating to and regulating motor-vehicles, which have been or may hereafter be paid into the State Treasury for registrations and license fees for the year beginning January first, one thousand nine hundred and seventeen, or which may be paid into the State Treasury from said sources thereafter, be, and the same are hereby, specifically appropriated to the State Highway Department, for the purpose of assisting in the construction, maintenance, improvement, and repair of State highways and State-aid highways, as described in the act of Assembly creating the State Highway Department, approved May thirty-first, one thousand nine hundred and eleven; said moneys to be paid from the State Treasury upon requisition of the Highway Commissioner and after audit and approval by the Auditor General and State Treasurer in the usual manner.
72 P.S. § 3441