Anyexcise officer who ceases or refuses to perform, or withdraws himself from, the duties of his office, unless he hadobtained the express written permission of his superior officer or has given such superior officer two months'notice in writing of hisintention or hasother lawfulexcuse, shall be punishable withimprisonment for a term which may extend to three months, or with fine whichmay extend to three months' pay, or with both.