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Show 702 MR. F. G. PARSONS ON THE [June 16, up to the external condyle of the femur; but, as the muscle has contracted attachments similar to those found in M a n to the fibula, the upper tendinous part of its origin takes on the function of a ligament. The muscle is inserted in the usual manner into the two outer toes. The Peroneus longus rises from the head and upper quarter of the fibula, as well as from the ligament already mentioned, belonging to the extensor longus digitorum. It is inserted into the entocuneiform. The Peroneus brevis is absent. Macalister, however, found it in the Great Kangaroo and Bennett's Wallaby. The Peroneus quarti cllgltl is very small and runs from the second quarter of the fibula to the great fourth toe. The Peroneus quinti digiti equals the peroneus longus in size; it rises from the upper third of the fibula and runs to the outermost toe. All three peroneals pass through the same synovial sheath and groove on the back of the external malleolus. The Gastrocnemius has the usual two heads, tbe outer of which has three origins : (1) a small head from the outer side of the patella; (2) larger, from the same place, and separated from the last by the external popliteal nerve ; (3) from the large fabella over the external condyle and from the external semilunar cartilage. The inner head is normal in origin and has no fabella developed in it. The Soleus is absent, unless the origin of the gastrocnemius from the semilunar cartilage represents it. Meckel also describes it, as wanting. Macalister found the fibular head in the Great Kangaroo and Bennett's Wallaby. The Plantarls comes from the external fabella and the back ot the external condyle ; it soon forms a tendon which passes round the tuberosity of the calcaneum, after which it divides into a large internal and a small external portion. The small slip runs to the outer toe, is pierced bv the flexor longus digitorum tendon, and is inserted into the outer side of the second phalanx. The large inner portion gives off a tendon from its outer side which is attached to both sides of the proximal phalanx of the outer toe, being perforated in its course by the last-named slip as well as by the tendon of the flexor longus digitorum to that toe. The main part of the inner portion goes to the proximal and distal phalanges of the great fourth toe. The Flexor longus digitorum (Flexor tibialis).--There is only one deep flexor at the back of the leg, which comes from about a third of the tibia and fibula below the popliteus. In the sole it divides into three tendons, of which the innermost again subdivides tor the two small inner toes. There are only two Lumbricales. The Popliteus rises from the external condyle, partly from in front of the groove and partly from the groove itself, which is deep and narrow, and not adapted"for the tendon to lie in. The muscle also has an origin from the external semilunar cartilage and from |