702 MR. F. G. PARSONS ON THE [June 16, 
up tothe external condyle of the femur; but, as the muscle has 
contracted attachments similar to those found in Man 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 digitt 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, the 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 Plantaris comes from the external fabella and the back of 
the external condyle; it soon forms a tendon which passes round 
the tuberosity of the caleaneum, after which it divides into a large 
internal and a small external portion. The small slip runs to the 
outer toe, is pierced by 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 Flevor 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 for 
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 
