CHAP, xiv MUSCLES AND EXERCISE 197 



IV. MUSCLES OF THE UPPER EXTREMITIES. 



24. Pectoralis, draws the arm forward and brings it across 



the chest. 



25. Deltoid, raises the arm at right angles to the trunk. 



26. Serratus magnus, moves the shoulder forward and upward. 



With the trapezius it is used in supporting a weight on 

 the shoulder and in pushing. 



27. Teres major, aids in rotating and drawing the arm down- 



ward and backward. 



28. Biceps, bends the arm at the elbow. 



29. Triceps, straightens the arm at the elbow. 



30. The flexors and extensors, move the hand, wrist, and 



fingers. 



V. MUSCLES OF THE LOWER EXTREMITIES. 



, . i i , T , 



pelvis, rotate the thigh inward, and aid 



r 



These muscles bend the thigh upon the 

 Iliacus 



35. Gracilis 



36. Gluteus 



33- Pectmeus 



in holding the body erect. 

 34. Adductors 



These muscles straighten the thigh at the 

 pelvis, rotate the leg, and aid in standing 



37. Biceps j erect. 



38. Sartorius, flexes the thigh upon the pelvis and rotates 



the thigh outward. 



39. Quadriceps, straightens the leg at the knee, and aids in 



stooping and standing. 



40. Gastrocnemius ^ 



41. Tibialis j These muscles aid in flexing and ex- 



42. Peroneus tending the foot, in bending the 



43. Soleus I knee, and are used in standing, walk- 



44. Extensors ing, and running. 



45. Flexors 



The hand and foot have numerous small muscles 

 which make a great variety of movements possible in 

 the fingers and toes. The hand alone has over thirty 

 muscles and the foot nearly as many. 



