A one year-old Collie was submitted to Stange Memorial Clinic on Feb. 7, 1952. for treatment of a head injury. The owner stated that the dog had been kicked in the head by a horse two months previously. The patient had a fistulous opening at the prominence of the right frontal bone which was discharging a thick, greenish-yellow purulent exudate. The diagnosis was impression fracture of the frontal bone with secondary frontal sinusitis.