Cystic tumors of the ovary arising from the graafian follicle are common. Small cystic degenerations of the corpus luteum are not uncommon, but a single cyst of any appreciable size is very unusual, although cysts "the size of a child's head" have been described.1Hertzler2states that these cysts develop because of the failure of the luteal cells to form fibrous tissue and the resultant corpus albicans—"at any rate the luteal cysts must be due to some disturbance in the physiology of ovulation. The result is a cyst seldom larger than a walnut, usually not larger than a hazelnut. Having attained this size, they may remain unchanged and symptomless, or hemorrhages may take place in them." REPORT OF CASE History.— Miss R. G., a white American office worker aged 34, was perfectly healthy until February 1938, when bilateral tubal abscesses developed and drained through the vagina. There