Fifteen rabbits were allotted equally to three groups: (I) two successive ejaculations every 48 hr, (II) sexual rest, and (III) unilateral vasectomy followed by sexual rest. One month later they were killed. Acid phosphatase was found in the Golgi area of epididymal columnar cells. Scattered columnar cells with intense acid phosphatase activity were also found in epididymal regions 1 and 6 and they were most numerous after vasectomy. Alkaline phosphatase was found apically in epididymal columnar cells and in their stereocilia. The weaker reaction in the proximal ductus deferens and epididymal regions 7 and 8 of the ejaculated rabbits supports the concept that regular ejaculation diminishes the rate of sperm resorption within the epididymis. The ampullae of ejaculated rabbits contained more alkaline phosphatase than those of non-ejaculated animals. Cytoplasmic pas-positive droplets were most abundant in regions 1 and 7 of the epididymis. Glycogen was found only in region 6. Little evidence was found for a holocrine cell cycle in the epididymis. Large, pas-positive cells, considered to be phagocytes, were most common in regions 1 and 6 of the epididymis and were present in increased numbers after vasectomy. Phagocytes may resorb materials emanating from the testis.