230 ANATOMY OF THE RABBIT. 
The tibial nerve lies on the medial surface of the head of the plan- 
taris and afterwards on the medial surfaces of the popliteus and flexor 
digitorum longus. 
5. Muscles arising from the foot and inserted on the individual 
digits. 
(a) The lumbricales. Origin: Tendon of the flexor digitorum 
longus. Insertion: Medial surfaces of the first phalanges 
of the three lateral digits. 
(b) The interossei (metatarsi). Origin: From the dorsal 
portion of the tendon-sheath of the flexor digitorum longus. 
Insertion: Heads of the four metatarsals. 
VESSELS AND NERVES OF THE LEG AND Foot. 
*The great saphenous artery passes distad on the medial 
surface of the leg, and is continued as the posterior tibial artery 
(a. tibialis posterior) around the medial malleolus to the plantar 
surface of the foot. Above the ankle-joint it gives off the malleolar 
artery (a. malleolaris) to the posterior surface of the distal end of 
the tibiofibula. 
The popliteal artery, the continuation of the femoral, passes 
between the medial head of the gastrocnemius on the one hand and 
the lateral head and the plantaris on the other, reaching the anterior 
surface of the popliteus, and afterwards the anterior surfaces of the 
tibia and fibula by passing between their proximal ends. It dis- 
tributes branches to the muscles about the knee-joint, including a 
branch to the distal portion of the vastus lateralis, which is given 
off at about the point of origin of the small saphenous artery. 
It then continues as the anterior tibial artery. The vessel 
appears in front of the interosseous ligament of the leg and of the 
peronaeus brevis, and continues to the dorsum of the foot after 
passing beneath the crural ligament. <A large branch, given off in 
the upper part of the leg also reaches the dorsum of the foot from a 
more lateral position. 
The small saphenous artery (a. saphena parva) appears on the 
proximal portion of the posterolateral margin of the leg, running 
along the border of the lateral head of the gastrocnemius in company 
with the corresponding vein and the lesser saphenous nerve. 
