The effects of ligation of an isolated loop of the ductus epididymidis in the region of the caput were compared with those of the exfoliative lesion of the epididymis that follows administration of \ g=a\ \ x=r eq-\ chlorhydrin to rats. Electron micrographs of the ductuli efferentes in both cases revealed early phagocytosis of apparently normal spermatozoa by the epithelial cells, followed at later intervals by invasion ofmacrophages and intraluminal phagocytosis. It is concluded that

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... spermiophagy is a consequence of obstruction, whether mechanically or chemically induced. Anita P. Hoffer et al. suture in order to compare the effects of chemically and mechanically induced obstruction of the initial segment.