A female Persian cat, eight years of age, was presented at the McGinnis Animal Hospital, Peoria, Ill., on July 6, 1940. The owner had noticed an enlargement of the abdomen with symptoms of anorexia, vomit ion and depression. The abdomen was enormously enlarged and the animal was emaciated. The temperature was 103°. A tentative diagnosis of pyometra was made and permission was granted to proceed with surgery.