Placed on the outer and posterior part of the fore-arm.
Origin.-From the point of the ridge on the outer and inferior extremity of the humerus.
Insertion. - By two tendons - (l) a broad flat one into the upper border of the pisiform bone; (2) a short round one into the head of the external small metacarpal bone. The latter passes over a groove and through a synovial sheath on the outer surface of the pisiform bone.