By plasma clot suture it has been found possible in certain cases to effect better restoration of the anatomic relationships of nerve stumps with less trauma to them than with the aid of silk.1However, owing largely to imperfections in technic, our earlier experiments were not uniformly successful. It soon became clear that plasma clot was suitable as suture material only when the nerve ends could be united without tension. It developed that further requisites for satisfactory suture by means of a plasma clot are: freedom from hemorrhage and contusion around the site of suture; procurement of flat, smooth contact surfaces of the nerve stumps so that satisfactory coaptation of fibers can be obtained, and the use of a removable mold which permits the plasma to surround uniformly the entire site of suture. The results of our efforts to bring about these favorable conditions for plasma clot suture of