Accelerators or the urine, (from accelero, to hanten). Called also urine stimulatores. They hasten the"ejection of the urine and semen.

The acceleratores urine arise fleshy from the sphincter ani, and superior part of the urethra, and tendinous from the ischium. They are inserted into the corpus cavernosum, from near their beginning to a little below their union. Douglas.

Dr. Hunter observes, that the acceleratores urine are fixed to and surround the bulbous part of the urethra, meeting in a middle line or tendon at its external posterior part. They are blended, at the end of the bulbous part of the urethra, with the other muscles of the part; when these muscles are put into action, they contract upon the urethra, thereby making it narrower, and expelling the last drops of urine. The semen also meets with a fresh impulse from these muscles contracting upon it, when it is in the bulbous part of the urethra; and this seems the chief reason of its being larger in one part than another, that the semen and urine may meet with a reservoir in their passage, where they found a fresh contracting force or power to forward their expulsion.