An employee or employees of the state, or of any county, city or of any institution supported in whole or in part by public funds, or any subdivisions thereof, may authorize the deduction from their salary or wages of the amount of their subscription payments to any corporation operating a nonprofit hospital service plan or medical service plan or pharmaceutical or optometric service plan, as provided in this chapter. The governing body of the state, or of the county, city or of any institution supported in whole or in part by public funds, or any subdivisions thereof, may authorize deductions from the salaries or wages of employees subscribing to such nonprofit hospital service plan or medical service plan or pharmaceutical or optometric service plan. The authorization by an employee or employees for deductions from the employee’s or employees’ salaries or wages shall be evidenced by a written request signed by the employee directed to and filed with the treasurer of the state, county, city or of any institution supported in whole or in part by public funds, or any subdivisions thereof, and said treasurer is authorized to draw and deliver checks in favor of the hospital service corporation or medical service corporation or pharmaceutical or optometric service corporation stipulated in such authorization for the amount covering the sum total of the deductions authorized. The foregoing provisions are not to be deemed an assignment of salaries or wages.