Pennsylvania constitution
Article V: the judiciary
Section 15

Until otherwise provided by law, the offices of prothonotary and clerk of courts shall become the offices of prothonotary and clerk of courts of the court of common pleas of the judicial district, and in multi-county judicial districts of their county's branch of the court of common pleas, and the clerk of the orphans' court in a judicial district now having a separate orphans' court shall become the clerk of the orphans' court division of the court of common pleas, and these officers shall continue to perform the duties of the office and to maintain and be responsible for the records, books and dockets as heretofore. In judicial districts where the clerk of the orphans' court is not the register of wills, he shall continue to perform the duties of the office and to maintain and be responsible for the records, books and dockets as heretofore until otherwise provided by law.