THE MUSCLES IO3 



(75) Pectineus (Fig. 49); cranial border of pubis to shaft of 

 femur; adductor of thigh. 



(76) Iliopsoas (Fig. 49); corresponds to human psoas and 

 iliacus; psoas portion arises by ten vertebral heads, the iliacus 

 portion from the ventral border of ilium; both parts converge 

 to insert in apex of lesser trochanter of femur; rotator and flexor 

 of thigh. 



(77) Capsularis (gluteus qiiarttis, epimeralis); ilium to dorsal 

 surface of femur; rotator of thigh (Fig. 51). 



(78) Quadriceps femoris ; consists of four muscles and may 

 be compared with triceps brachii of forelimb. 



(a) Rectus femoris (Figs. 57, 5^); ilium near acetabulum to 

 outer, proximal surface of patella. 



(b) Vastus lateralis (Figs. 50, 51) ; great trochanter and surface 

 of femur to outer, lateral surface of patella. 



(c) Vastus medialis (Fig. 49) {crural) ; shaft of femur to outer, 

 medial surface of patella. 



{d) Vastus intermedius; dorsal surface of femur to capsule 

 of joint. Entire group acts as extensor of shank; the inter- 

 medius alone acts as tensor of capsule. 



MUSCLES OF SHANK OR LOWER LEG 



(79) Gastrocnemius (Figs. 49, 50) arises by two heads; 

 caput laterale has four origins: (a) superficial fascia; (h) lateral 

 sesamoid bone of femur; {c) tendon of plantaris; {d) aponeurosis 

 covering plantaris; caput mediate from medial sesamoid bone 

 of femur and surface of femur; both heads unite in a tendon 

 which forms part of the tendon of Achilles and inserts onto the 

 proximal end of the calcaneus; extensor of foot. 



(80) Plantaris (Figs. 50, 58), lateral border of patella and 

 lateral sesamoid bone to the plantar aponeurosis which gives 

 origin to the flexor brevis digitorum; flexor of digits. Its tendon 

 passes down through a sheath formed by the gastrocnemius 

 and soleus and over the insertion of the tendon of Achilles 

 (tendo calcaneus). 



