Ultrasound and histological sections were taken of 34 prostate units removed from fresh cadavers. Ultrasonography seems to raise more problems than it solves; only 73% of the normal prostates were homogeneous under ultrasound. Ultrasonography visualized nodular structures requiring biopsy in 71% of the cases of prostatic adenoma. There were too few cases of malignant tumors in the sample to warrant a conclusion. They were highly evolved. Ultrasonography gave strong grounds for suspicion, but they could be easily diagnosed clinically.