All directors, officers, and employees of an association shall, before entering upon the performance of any of their duties, execute their individual bonds with adequate corporate surety payable to the association as an indemnity for any loss the association may sustain of money or other property by or through any fraud, dishonesty, forgery or alteration, larceny, theft, embezzlement, robbery, burglary, holdup, wrongful or unlawful abstraction, misapplication, misplacement, destruction or misappropriation, or any other dishonest or criminal act or omission by any such director, officer, employee, or agent. Associations which employ collection agents, who for any reason are not covered by a bond as hereinabove required, shall provide for the bonding of each such agent in an amount equal to at least twice the average monthly collection of such agent. Such agents shall be required to make settlement with the association at least monthly. No bond coverage will be required of any agent which is a financial institution insured by the Federal Deposit Insurance Corporation or by the federal savings and loan insurance corporation. The amounts and form of such bonds and sufficiency of the surety thereon shall be approved by the board of directors and by the commissioner. In lieu of individual bonds, a blanket bond, protecting the association from loss through any such act or acts on the part of any such director, officer, or employee, may be obtained. Such bonds shall provide that a cancellation thereof either by the surety or by the insured shall not become effective unless and until ten days' notice in writing first shall have been given to the commissioner unless the commissioner shall have approved such cancellation earlier.