The case of urethral calculus to be reported here is of interest because of the absence of symptoms in spite of the large size of the stone and because it demonstrates the value of urethrography for localization and evaluation. Case Report A 53-year-old white male was referred for roentgen examination of the perineal region because of his accidental palpation of a perineal mass during bathing. His past history was entirely non-contributory, revealing no urinary tract abnormality or infection. Physical examination disclosed the presence of a fixed, stony hard perineal mass, immediately posterior to the scrotum; its precise dimensions could not be determined. Otherwise the physical findings were normal. Digital rectal examination demonstrated a prostate of normal size and consistency. Except for the presence of small numbers of polymorphonuclear leukocytes in the urine, laboratory studies were also normal. Radiographic examination of the pelvic region revealed a large, oval, lamellated calculus in the subpubic region (Fig. 1). Study in the lateral and oblique planes confirmed its anterior and subpubic location. It was believed to be a calculus located in a urethral diverticulum. Urethrography was recommended, both to confirm the location of the stone and to determine whether or not urethral stricture was present. Urethrography was performed on Feb. 7, 1951, under fluoroscopic guidance. Rayopake, injected intra-urethrally, through an attached Brodny clamp, passed through the urethra adjacent to the calculus into the bladder. Film study confirmed its apposition to the membranous urethra. No stricture was demonstrable. There was minimal elongation of the prostatic urethra (Figs. 2 and 3). Immediate operation was recommended, but was postponed by the patient. On March 14, 1951, he reported with perineal induration and inflammation, with fluctuation superficial to the calculus. He was hospitalized on March 16, and on March 17 spontaneous superficial drainage occurred. Under spinal anesthesia, the area of spontaneous perforation was enlarged and explored by Dr. James Lehman. The calculus could not be palpated and it was believed to have passed spontaneously. Iodoform packing was inserted. Postoperative roentgen examination, however, again revealed the calculus. On March 27, under spinal anesthesia, with an intra-urethral catheter present, a transverse perineal incision was made. The transverse perinei muscles were divided, and the calculus was palpated in the membranous urethra just distal to the prostate. A longitudinal incision was made in the urethra and the calculus removed. The urethra was sutured around the indwelling catheter, an iodoform pack drain was inserted, and several interrupted silk sutures were introduced in the skin. The calculus was 4.2 cm. long, 3.0 cm. wide, and 2.5 cm. in anteroposterior diameter (Fig. 4). Penicillin was given preoperatively and postoperatively.