THE MUSCULAR SYSTEM 



65 



also assists the other muscles of the chest, as in climbing, 

 pulling, etc. 



FIG. 34. Muscles of the trunk from behind (left side, superficial ; right 

 side, deep): i, Sternomastoid ; 2, splenius ; 3, trapezius ; 4, latissimus 

 dorsi ; 5, infraspinatus ; 6, teres minor; 7, teres major; 8, deltoid; 9, ex- 

 ternal oblique of abdomen; 10, gluteus meclius ; n, gluteus maximus ; 12, 

 levator anguli scapulae; 13, rhomboideus minor; 14, rhomboideus major; 

 15, part of longissimus dorsi; 16, tendons of insertion of iliocostalis ; 17, 

 supraspinatus ; 18, infraspinatus ; 19, teres minor; 20, teres major; 21, ser- 

 ratus magnus ; 22, upper, and 22', lower part of serratus posticus inferior ; 

 23, internal oblique ; 24, gluteus medius ; 25, pyriformis and superior and 

 inferior gemelli ; 26, 26', portions of obturator internus ; 27, tendon of obtu- 

 rator internus ; 28, quadratus femoris. 



(The student should refer to the illustrations, noting 

 the relation that the several muscles bear to the act of 

 respiration, as well as the number that are concerned in the 

 act of moving the trunk in various positions.) 

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