The epididymal secretions in cases of obstructive azoospermia, where the site of obstruction was distal to the body of the epididymis, were studied by means of new staining techniques for the detection of spermiophage cells. The spermiophage cells were rich in lipoid material which resembled the pigment lipofuscin. Results of such staining demonstrated that phagocytosis was the chief mechanism involved in the disposal of dead spermatozoa in the majority of such cases. Study of epididymal biopsies in these cases demonstrated that the sperm phagocytosis was chiefly intraluminal and the occurrence of extravasation of spermatozoa in the interstitial tissues of the epididymis was a rare phenomenon. Evidence is presented to show that the spermiophage cells are derived from the basal layer of cells lining the epididymal tubules and in some instances the columnar epithelial lining of the epididymal tubules manifested phagocytic properties. The possible significance of this finding, and its role in the development of auto-antibodies against spermatozoa in the host, is discussed.