Situated behind the fore-arm to the outer side of the preceding muscle. It is divided above into two parts, the posterior of which is the smaller.

Origin. - By its anterior and larger division from the internal condyle of the humerus immediately behind the internal flexor. By its posterior division from the upper and posterior part of the point of the elbow (olecranon).

Insertion. - Into the upper border of the pisiform bone.

Action. - To bend the knee.