§ 12. Deputy adjutant general. There shall be a deputy adjutant general who shall serve as such at the pleasure of the governor. The deputy adjutant general shall be appointed by the governor from among the commissioned officers on the active list of the organized militia upon the recommendation of the adjutant general and, while holding such title, shall have the rank of a general officer or flag officer. He shall have such duties as may be prescribed by the adjutant general and shall act in place of the adjutant general during his absence or disability.