63 STAT.] 81ST CONG. , 1ST SESS.-CH. 393-AUG. 4, 1949 from among the groups set forth in section 225 of this title as deter- mined by the Secretary, such officer shall be appointed by the President, by and with the advice and consent of the Senate. (b) The Secretary may prescribe regulations dealing with the filling of vacancies by appointment, including, but not limited to, the scope and method of conducting professional and physical examinations and the passing marks required. (c) Any person thus appointed as a permanent commissioned officer shall take precedence in the grade in which he is appointed in accord- ance with the date of his commission as a permanent commissioned officer in such grade. Appointees whose dates of commission are the same shall take precedence with each other as the Secretary shall determine. § 225. Permanent appointments (a) The President may appoint, by and with the advice and consent of the Senate, permanent commissioned officers in the Coast Guard in grades appropriate to their qualifications, experience, and length of service, as the needs of the Coast Guard may require, from among the following categories: (1) graduates of the Coast Guard Academy; (2) temporary commissioned officers of the Coast Guard who have served at least two years as such; (3) commissioned warrant officers, warrant officers, and enlisted men of the Coast Guard; (4) members of the Coast Guard Reserve who have served at least two years as such; and (5) licensed officers of the United States Merchant Marine who have served four or more years aboard a vessel of the United States in the capacity of a licensed officer, but any person of this category, commissioned pursuant to this section, shall serve a probationary period of two years, during which time his commis- sion may be revoked if his services are unsatisfactory, under such regulations as the Secretary shall prescribe. (b) No person shall be appointed a commissioned officer until his mental, moral, physical and professional fitness to perform the duties of a commissioned officer has been established as the result of such examinations as the Secretary shall prescribe. § 226. Temporary appointments (a) The Secretary may appoint temporary commissioned officers in the grade of lieutenant commander or below, appropriate to their qualifications and experience, who, while in service, shall receive the same pay, allowances, and benefits as permanent commissioned officers of corresponding grade and length of service, except that no temporary commissioned officer as such shall be entitled to retirement while serv- ing under his temporary commission. Temporary appointments shall be made only after the candidate has satisfactorily passed such exami- nation as the Secretary shall prescribe. The names of all persons who are appointed temporary commissioned officers shall be placed on a special list of temporary commissioned officers, as distinguished from the list of permanent commissioned officers. (b) Any warrant officer or enlisted man in the regular Coast Guard may be appointed as a temporary commissioned officer. Notwithstand- ing such temporary appointment, any such warrant officer or enlisted man shall be entitled to retirement in his permanent grade or rating in the same manner as though he had continued to hold his permanent grade or rating, and upon the termination of such temporary appoint- ment shall be entitled to revert to such grade or rating. Service under 81939--50 -PT . --- 33 513 Lieutenant com- mander or below. Warrant officer or enlisted man.