TRAPEZIUS MUSCLE. 



355 



ribs is moved upwards and towards the spinal column ; but the upper fibres 

 can assist other muscles in elevating, and the lower fibres will help in 

 depressing that bone. 



When the scapula is prevented from gliding on the ribs, the trapezius 

 imparts a rotatory movement to it, and raises the acromion. 



Fig. 116. 



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JD 



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O 



ctf 

 O 



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MUSCLES OF THE BACK. On the left side the first layer is shown, and on the right side the second 

 layer, with part of the third. 



A. Trapezius. E. Khomboideus major. 



B. Latissimus dorsi. F. Splenius. 



c. Levator anguli scapulae. o. Serratus posticus inferior. 



D Rhomboideus minor. 



Dissection. The fibres of the trapezius are to be divided near the sca- 

 pula, over the situation of the spinal accessory nerve, so that the ramifica- 

 tions of that nerve in the muscle, and its junction with the branches of the 

 cervical plexus may be observed. A small artery to the trapezius (art. 

 superficialis colli) accompanies the nerve. 



