The daily glycogen content of the uterus, cervix, upper and lower vagina and abdominal muscle of the hamster during the 4-day cycle was determined quantitatively by the anthrone method and localized histochemically with the PAS reaction. The amount of glycogen was maximal in the cervical and upper vaginal tissue on Day 1, the day preceding ovulation. While uterine and vaginal glycogen also increased significantly on Day 1, the increases were not as great as in the other portions of the tract.