In the event of the death of any supernumerary magistrate in whose favor a monthly retirement allowance is accruing, his spouse shall be entitled to a monthly allowance equal to 50 per centum of the retirement allowance the supernumerary magistrate was receiving when he died, as hereinafter specified, for a period of up to 25 years. No spouse shall receive any benefits under this article unless such spouse was married to the deceased supernumerary magistrate at the time of his death and any benefits of a spouse under this article shall terminate in the event the spouse remarries.