(1) The warden of the state penitentiary shall receive a salary payable monthly upon the warrant of the commissioner of finance and administration.
(2) The salaries of all superintendents shall be fixed by the commissioner vested with the administration of the respective institutions, unless otherwise fixed by law before the appointment of such superintendent, and the same shall not be changed during their terms of office.
(3) The commissioner shall file with the commissioner of finance and administration a statement in writing showing the salaries of such other superintendents, and the same shall be paid monthly upon the warrant of the commissioner of finance and administration.