This fleshy portion, situated behind the preceding, arises from the superior extremity of the tibia, on the borders of the groove in which the tendinous portion lies; thence it passes downwards for a short distance on the inner side of the common extensor of the toes, which covers it in the rest of its extent. It ends in a tendon which, after passing through the tendinous ring above noticed, divides into two branches. One of these branches is inserted into the anterior surface of the superior extremity of the principal metatarsal, the other into the second cuneiform bone. [Illustration: FIG. 84.--MYOLOGY OF THE DOG: LEFT HIND-LIMB, EXTERNAL ASPECT. 1, Biceps cruris and fascia lata, divided in order to expose the upper part of the muscles of the leg; 2, inferior portion of the triceps cruris; 3, patella; 4, semi-tendinosus; 5, inferior extremity of the femur; 6, tibialis anticus (flexor of the metatarsus); 7, extensor longus digitorum (anterior extensor of the phalanges); 8, tibia; 9, peroneus longus; 10, peroneus brevis; 11, fifth metatarsal; 12, fasciculus detached from the peroneus brevis and passing towards the fifth toe; 13, external head of gastrocnemius; 14, tendo-Achillis; 15, calcaneum; 16, flexor digitorum sublimis; 17, 17, tendon of the flexor digitorum sublimis; 18, flexor longus pollicis (portion of the deep flexor of the toes); 19, dorsal muscle of the foot (short extensor of the toes).] In the ox the same two portions of the tibialis anticus exist, but with this capital difference--that the anterior portion is fleshy, superficial, and blended for a great part of its length with the common extensor of the toes. The portion which corresponds to that which is fleshy in the horse arises from the tibia; below, it ends on the inner surface of the superior extremity of the metatarsus and the cuneiform bones. That which represents the tendinous part, which is also fleshy, as we have just pointed out, arises above with the common extensor of the toes, from the femur, in the fossa situated between the trochlea and the external condyle; whilst below, after having given passage to the tendon of the preceding portion, as in the horse, it is inserted into the metatarsus and the cuneiform bones. In the pig, the tibialis anticus presents an arrangement nearly similar to that which we have just described. It seems to us of interest to add that it has been sought to ascertain to what muscle of the human leg the tendinous part of the tibialis of the horse corresponds--a part which has become fleshy in the pig and the ox.