Development of the Fertilizing Ability of Spermatozoa in the Epididymis of the Syrian Hamster

Summary. Hamster epididymal spermatozoa do not normally acquire the ability to penetrate eggs until they reach the proximal portion of the cauda epididymidis. Careful ligation of the lower corpus epididymidis for 3 to 5 days produced some improvement in the motility but a failure of the fertilizing ability of spermatozoa withheld proximal to the ligature. These findings are compared briefly with those in the rabbit, in the light of the character of the epithelium in the different macroscopic regions of the epididymis in the two species.