After so full a consideration of the surgical injuries of the head, trunk and upper extremities, we are somewhat surprised to find Gilbert's discussion of the similar injuries of the lower extremities condensed into a single very moderate chapter entitled "De vulneribus cruris et tybie" (f. 358a b). In this, Gilbert, emphasizing the importance of wounds of the patella and knee-joint and the necessity for their careful treatment, also declares that wounds of both the leg and thigh within three inches of the joints, or in the fleshy portion of the thigh _ubi organum est_ (?), involve considerable danger. He then speaks of a blackish, hard and very painful tumor of the thigh, which, when it ascends the thigh (_ad superiora ascendit_) is mortal, but if it descends is less dangerous. Separation of the sacrum (_vertebrum_) from the ilium (_scia_), either by accident or from the corrosion of humors, leaves the patient permanently lame, though suitable fomentations and inunctions may produce some improvement. Sprains of the ankle are to be treated by placing the joint immediately in very cold water _ad repercussionem spiritus et sanguinis_, and the joint is to be kept thus refrigerated until it even becomes numb (_stupefactionem_); after which stupes of salt water and urine are to be applied, followed by a plaster of galbanum, opoponax, the apostolicon, etc. Fractures of the femur are to be treated like those of the humerus, except that the ends of the fractured bone are to be separated by the space of an inch, and a bandage six fingers in width carefully applied. Such fractures within three inches of the hip or knee-joint are regarded as specially dangerous. Dislocations of the ankle, after reduction of proper manipulation, should be bound with suitable splints. If of a less severe character, the dislocation may be dressed with stupes of canabina (Indian hemp), urine and salt water, which greatly mitigate the pain and swelling. Afterwards the joint should be strapped for four or five inches above the ankle with plaster, _ut prohibeatur fluxus_. It should be said that the brevity of this chapter of Gilbert is modeled after the manner of Roger of Parma, who refers the treatment of injuries of the lower extremities very largely to that of similar injuries of the upper, merely adding thereto such explanations as may be demanded by the differences of location and function of the members involved. Thus in his discussion of dislocation of the femur Roger says: _Si crus a coxa sit disjunctum, eadem sit cura quam et in disjuncturam brachii et cubiti diximus, etc._