The powers of co-trustees are usually spoken of as "joint," while the powers of co-executors are commonly referred to as "joint and several." As it is fairly obvious that if executors have a several power they may also exercise it jointly, it might be preferable to refer to the powers of co-executors as "joint or several." For not all the powers of a co-executor are joint and several. Some are several, while others are only joint. The general rule is that a co-executor has the several power to bind the estate as to matters in the ordinary course of administration, while certain powers which involve judgment and discretion must be exercised jointly.