For two years I have been experimenting on dogs with the object of determining whether the complete removal of the bladder can be made a justifiable operation. In order to make removal of the bladder an acceptable procedure it is necessary to dispose of the ureters in a manner so that the substitute receptacle for the urine will have reservoir room, contractile power under the control of the individual, and, most important, a perfect sphincter outlet, also under the complete control of the individual. Reserving the history of the work already done in this comparatively new field for a subsequent paper which I now have in preparation, which also will give my many experiments in detail, I will simply state that the rectum seems to offer a reservoir which fulfills the above indications. The reason why the lower bowel does not make an ideal bladder is because it is not