42 



ANATOMY FOR NURSES. 



[CHAP. IV. 



The thorax, or chest, is an elongated conical-shaped cage, 

 formed by the sternum and costal cartilages in front, the 

 twelve ribs on each side, and the bodies of the twelve dorsal 



IMESMRD. 



FIG. 42. THORAX. 1 to 12, ribs; d, d, costal cartilages ; e, upper end of sternum ; 

 6, middle portion of sternum; la, first dorsal vertebra; 12 a, twelfth dorsal verte- 

 bra ; 7 a, seventh cervical vertebra ; 1 to 7, true ribs ; 8 to 12, false ribs ; 11, 12, float- 

 ing ribs. 10th rib is defective ; it should be attached to the costal cartilage. 



vertebrae behind. It contains and protects the principal organs 

 of respiration and circulation. 



The sternum, or breast bone, is a flat narrow bone, situated 

 in the median line in the front of the chest, and consisting, 

 in the adult, of three portions. It has been likened to an 

 ancient sword. The upper piece, representing the handle, is 



