MUSCLES OF THE POSTERIOR LIMBS. 



303 



Ac(ion.-~T}ie gastrocnemii extend the foot upon the tibia. They act as 

 a lever ol the first order when the limb is raised from the ground, and as 



Fig. 137. 



MUSCLES ON INNER ASPECT OF LEET POSTEEIOK LIMB. 



1, Crest of the ilium ; 2, Section through it ; 3, Sacro-ischiatic ligament ; 4, Pyii- 

 formis ; 5, Posterior portion of sacro-ischiatic ligament ; 6, Tuberosity of ischium ; 

 7, Anterior portion of ischium, sawn through ; 8, Pubis ; 9, Obturator foramen ; 

 10, External iliac artery and v.ein, 11 ; 12, Obturator artery and vein ; the figures 

 are placed on the internal obturator muscle ; 13, Long adductor of the leg, or 

 sartorius ; 14, Small adductor of the thigh, or adductor brevis ; 15, Short 

 adductor of the leg, or gracilis; 16, Rectus of the thigh; 17, Vastus internus;' 

 18, Patella, with insertion of rectus ; 19, Upper .extremity of tibia; 20, Gas- 

 trocnemius; 21, Popliteus; 22, Oblique flexor of the phalanges, or flexor pedis 

 accessorius, with its tendon, 34; 23, Perforans muscle, with its tendon, 35; 24, 

 Flexor metatarsi; 25, Anterior extensor of the phalanges, or extensor pedis; 

 26, Annular ligament ; 27, Tendon of flexor metatarsi, and its cunean branch, 

 28 ; 29, Tendon of superficial flexor or internal gastrocnemius ; 30, Tendon of 

 gemelli or external gastrocnemius ; 31, Os calcis ; 32, Astragalus ; 33, Perforatus 

 tendon ; 34, Tendon of oblique flexor joining the perforans tendon, 35 ; 36, Laf'ge 

 metatarsal bone ; 37, Extensor pedis tendon; 38, Terminal knob of small meta- 

 tarsal bone. 



