176 



MUSCULAR SYSTEM. 



whole body in progression, and this organ is strengthened by 

 its shortness, and by the fixed condition of its solid parts. The 

 gastrocnemii, (79. B. k, I,) are large, and the tendo achilles, 



FIG. 79. 



(, 



(79. B. m,) is thick and strong, to raise the heel and the 

 whole trunk in walking, and to preserve the tibia in a vertical 

 position on the astragalus in standing. For the same reason 

 the rectus femoris (79. A. n,) and the vastus exturnus (J9. A. 

 nf) and interims (79. A. w,f) are large and fleshy, to preserve 

 the femur erect upon the tibia, and the glutei muscles (79. B. 

 /,) are of great magnitude, to preserve the pelvis and trunk 

 vertical upon the femur. Hence the magnitude and rotun- 

 dity of the calfs, the thighs, and the nates, so characteristic 



