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Life and Health 



forward. At the back of the shoulder a large, spread-out 

 muscle passes upward from the back to the humerus. 

 From its wide expanse on the back it is known as the 

 latissimus dorsi ("broadest of the back"). When in action 



FIG. 35. Principal Muscles on the Left Side of Neck. 



A, buccinator; ff, masseter; C, depressor anguli oris; D, anterior portion of the 

 digastric; E, mylo-hyoid ; F, tendon of the digastric ; G, sterno-hyoid ; //, sterno- 

 thyroid; K, omo-hyoid; /., sternal origin of sterno-cleido-mastoid muscle; 

 M, superior fibers of deltoid; N, posterior scalenus; O, clavicular origin of 

 sterno-cleido-mastoid ; P, sterno-cleido-mastoid ; R, trapezius ; S, anterior con- 

 strictor ; T, splenius capitis ; V, stylo-hyoid ; W, posterior portion of the 

 digastric; X, fasciculi of ear muscles; Z, occipital. 



it draws the arm downward and backward, or, if one hangs 

 by the hands, it helps to raise the body. It is familiarly 

 known as the " climbing muscle." 



