No child shall be prosecuted for any offence except on the instructions of the Lord Advocate, or at his instance; and no court, other than the High Court of Justiciary and the sheriff court, shall have jurisdiction over a child for an offence.

The case of any child liable to prosecution in respect of any act committed or omission made, but against whom proceedings have not been instituted before the commencement of this Act, shall be dealt with in accordance with the law as in force after the said commencement.

Part IV of the [1937 c. 37.] Children and Young Persons (Scotland) Act 1937 shall have effect subject to the amendments set out in Schedule 2 to this Act.