This latter was sometimes very marked, as in the case of all the other traumatic blood effusions, but not quite so regular in occurrence. It was important, as I have seen it give rise to the suspicion of suppuration, when tapping resulted in nothing more than the evacuation of turbid synovia mixed with blood. Pain was rarely a prominent symptom in consequence of the generally moderate degree of distension. As a rule, these injuries were characterised by the small tendency to the development of adhesions; but this in great part depended on the care expended on their treatment. If kept too long quiet, either from necessity when the effusion was followed by much thickening, or when the external wound was large and so situated as to be harmfully influenced by movement, or in the ordinary course of treatment, troublesome stiffness, even amounting to firm anchylosis, sometimes followed. I saw several such cases, some of the most confirmed being wounds of the knee-joint complicated by injury to the popliteal vessels or nerves. The latter complication I saw altogether six times, but only once with a thoroughly bad knee, and in this case the injury had affected both the vessels and the internal popliteal nerve. The joint in that case was straightened out by continuous extension by Major Lougheed, when it came under his charge some six weeks after the primary injury, but I hear has again relapsed, and the popliteal paralysis is not much improved. The small tendency to formation of adhesions in uncomplicated cases probably depended on the coagulation of a layer of blood over the whole internal lining of the joint. This kept the synovial surfaces apart at the lines of reflection of the membrane, and, given sufficiently active treatment, mobility was restored before any firm union could take place. The primary escape of synovial fluid was rarely observed, as the wounds of the soft parts were too small and valvular to permit of it. Synovia in some abundance, mixed with pus, sometimes escaped in considerable quantity when infection had opened up the tracks. Primary suppuration in any joint as a result of small and direct wounds was very rare. I observed it only on one occasion. On the other hand, a considerable number of cases in which secondary suppuration occurred came under my notice. In some of these the suppuration was secondary to comminuted fractures of the shaft of the tibia, in which the articular extremity was implicated. These offered no special peculiarity. In others infection of the joint was secondary to infection and suppuration in the deep part of long oblique wound tracks, and these were of sufficient interest to warrant the insertion of two illustrative cases.