Dec. 5, 1947, a 12 year old saddle mare was admitted to the Stange Memorial Clinic. On the dorsal surface of the third metatarsal bone, about 4 in. below the hock, was a large open wound from which a purulent exudate was draining. The leg was enlarged !rom the hock to the coronary band of the hoof, and at the location of the wound, the leg was almost twice its normal size.