The Muscles and Their Work. 29 



inal especially great muscular development in this region 

 is essential, as these muscles contribute largely to the 

 high priced cuts. 



The hip or croup is extended by the great rump muscle 

 (gluteus maximus), which also exists in rearing, and by 

 some muscles which lie at the back of the thigh bone 

 (femur). The great rump muscle is attached to the 

 upper portion of the pelvis (Ilium) and runs forward as 

 far as the last rib, its insertion being on the head of the 

 thigh bone. The muscles at the back of the thigh origi- 

 nate on the under surface of the pelvis from behind the 

 hip joint to the point of the buttock and are inserted 

 principally to the lower part of the thigh bone or the 

 upper portion of the bone below (the tibia). The hip 

 is flexed by muscles (psoae) that have their origin on 

 the under surface of the last dorsal vertebrae and ribs 

 and the loin; they also tend to arch the back and bring 

 the animal to its feet after rearing; the insertions are on 

 the thigh bone. Other muscles (triceps adductors femoris 

 sartorius and pectineus) which are attached to the under 

 surface of the pelvis in front of the hip joint, the thigh, 

 stifle and lower thigh also flex the hip. Some of these 

 muscles also draw the hind limbs outward (abduct) some 

 inwards (adduct). 



The stifle is extended by one muscle (rectus femoris) 

 which has its origin on the under surface of the pelvis 

 just in front of the hip joint, its insertion being to the 

 stifle. This muscle also flexes the hip. The stifle is 

 flexed chiefly by a muscle (biceps rotator tibialis) 

 attached to the pelvis behind the hip joint and to the 

 lower thigh (tibia) or gaskiu. 



