256 



PHYSIOLOGY AND HEALTH, 



ward and backward, as in the elbow, (Fig. XLIV.,) the knee, 

 (Fig. XL VII.,) and the connection of the lower jaw with the 

 he"ad. 



FIG. XLIV. Elbow. 



a, Bone of the tipper- arm. 



b, e, Bones of the fore-arm. 



c, Inner angle of the joint. 



d, Ligaments of the joint. 



The ball and socket joint is composed of aJball on the end 

 of one bone, and a cup or socket in the other, in which the 

 ball plays, as in the hip joint, (Fig. XLV. c, c?,) or as the 



Fm. XLV. Hip Joint. 



a, Hip bone. 



b, 6, Thigh bone. 



c,Head of the thigh 

 bone. 



d, Socket in the hip 

 bone. 



e, Ligament attached 

 to the bottom or centre 

 of the socket and the 

 head of the thigh bone. 



shoulder, or the attachment of the thumb to the hand. This 

 joint allows motion in every direction, forward and back- 

 ward, upward and downward, and in a circular manner. 



607. The thigh bone has almost a globular head at its up- 

 per extremity, (Fig. XLV. c,) which is fitted into a very deep 



