A fact of considerable importance in the interpretation of skiagraphs of fractures of the astragalus, is a knowledge of the presence in many normal individuals of a little bone known as the _os trigonum_. It may occur detached from the astragalus or may be attached to it as a process, on its posterior aspect, and on account of the swelling and pain around the ankle, a diagnosis can seldom be made without the routine use of the X-ray in every injury in this region. The swelling, with obliteration of the depressions normally present around the ankle, does not differ from that characteristic of a sprain of the ankle or of a Pott’s fracture. If there is extensive comminution of the os calcis or astragalus, the malleoli may be a little lower than normal. The X-ray must always remain our most reliable means of diagnosis at the time of the injury. At a later period the chief symptoms are a painful flat foot, ankylosis of the ankle joint, pain and difficulty in pronating and supinating the foot. The prognosis of fractures of the tarsal bones is not favorable, even though the lesion has been recognized at the time of injury. Even in the most favorable cases there is some limitation of lateral motion. The outlook is better in those cases of fracture of the os calcis in which there is a large heel fragment, than if the fracture is comminuted. The most frequent sequel is stiffness of the ankle-joint and traumatic pes valgus. Infection is frequent in compound fractures. +Treatment.+ This does not differ from that of a Pott’s fracture until the greater part of the swelling has disappeared. The skin of the foot and lower portion of the leg should be thoroughly cleansed and covered with gauze. This is necessary on account of the possibility of necrosis of the skin of the heel, and the danger of infection of the bruised soft tissues around the heel. The foot should be placed in a well-padded box or in a posterior splint of the Volkman type. Ice bags should be applied over the sides of the heel. After from eight to ten days, a circular plaster cast can be applied, extending from the toes to the knee. An anesthetic should be given during the application of the cast, the foot being held flexed at right angles and sheet wadding freely used around the ankle. The cast should be worn for seven weeks. At the end of this time the patient is gradually permitted to step upon the injured foot. Passive and active motion are also now employed. Fractures of the neck of the astragalus, with rotation of the posterior fragment, are usually followed by great limitation of the movements of the ankle joint. This condition might be greatly improved by an open operation. +Fractures of the Metatarsal Bones.+ These are usually due to direct violence, as occurs when a heavy weight falls upon the dorsum of the foot. Another example of direct violence is a fracture following a crushing injury, as in being run over.