18 PHYSIOLOGY. 



The Spine 



Is composed of the true and false vertebra. The true ver- 

 tebra comprise three classes. First, the cervical, which are 

 the seven uppermost vertebra belonging to the neck; the 

 first is called the atlas, the second the dentata. Second class, 

 the dorsal or those of the back, which are twelve in number. 

 And the third, the lumbar, or those of the loins, five in 

 number. 



The Thorax 



Is composed of the dor sal vertebra, twelve pair of ribs, with 

 their cartilages, and the sternum. 



The Pelvis 



Is composed of the false vertebra (the sacrum and coccy- 

 gis) behind, and the two ossa innominata at the side and in 

 front. 



The Members 



Comprise the two extremities ; the superior and inferior 

 extremity. 



The Superior Extremities, 



Each, consist of the shoulder, the arm, the fore-arm and 

 hand. 



The Shoulder 



Is composed of two bones ; the clavicle or collar bone, a 

 long bone, in front ; the scapula or shoulder blade, a flat bone 

 behind. 



The rfrm 

 Has one long bone, the humerus. 



The Fore Arm 

 Has two long bones, the radius and ulna. 



The Hand 



Comprehends the whole structure from the end of the fore 

 arm to the points of the fingers. It consists of the carpus or 

 wrist, the metacarpus or parts near the wrist, and the fingers 

 including the thumb. 



The Carpus 

 Is composed of eight small bones arranged in two rows. 



