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MAMMALIAN ANATOMY 



CHAPTEE VIII 



THE APPENDICULAR SKELETON THE THORACIC LIMBS 



FIG. 413. 



TRUNK. 



THE REGIONS OF THE SKELETON. 



The Appendicular Skeleton comprises the bony framework of the 

 Anterior or Thoracic and the Posterior or Pelvic Limbs. 



THORACIC LIMBS. 



Each Thoracic Limb consists of: 



(1.) A proximal portion, the shoulder, which is supported by the 

 shoulder girdle, an incomplete arch formed of the shoulder blade, or 

 scapula, and the collar bone, or clavicle, and embedded in the muscles 

 of the trunk ; 



(2.) A free portion, the part which alone is usually recognized as 

 the limb. This portion is divided into : 



(a) The Arm, which is supported by a single bone, the humerus ; 



(b) The Forearm, which has two long bones, the radius and the 



ulna, placed side by side ; 



(c) The Hand, which is subdivided into : 



The Wrist, or Carpus, with eight short carpal bones ; 



