Except as otherwise provided, a senior judge shall receive from the state an annual salary equal to two-thirds of the salary provided by law to be paid by the state to a judge of the superior court at the time of his appointment to the position of senior judge under this chapter. In addition to this salary, a senior judge shall receive from the counties of the circuit of which he had lately been judge a salary equal to two-thirds of the amounts which had been paid to him as judge by those counties at the time of his resignation as judge of the superior court and his appointment as senior judge.