A short stout muscle situated behind the leg. It consists of two separate portions, which converge and unite below to form a single strong tendon.

Origin. - From either side of the supracondyloid fossa at the lower and back part of the femur.

Insertion. - Into the middle of the summit of the os calcis, or point of the hock. A small synovial bursa is interposed between the anterior face of the tendon and the portion of the os calcis in front of it. By this means the parts move freely over each other when the hock is flexed.

Prior to its insertion into the point of the hock the tendon of this muscle is joined by that of another small muscle - the soleus.

Action. - To extend the hock.