The term posture indicates the relative situation of the several members of the body with regard to each other, or the relative situation of the parts of the member. Now, the posture is the result of the last movement; the description of a posture is the description of the effect of the last movement of the part. Postures may be seen as the result of the action of any part of the muscular system. We may speak of the posture of the hand and upper extremity, the head and neck, the back, &c. Postures depend upon the resultant action of opposing muscles, the relative tone of the flexors and extensors, the adductors and abductors, &c. In the limbs the opposing muscles act upon the bones and move the joints. In the face the contending muscles dilate and contract the apertures for the eyes, mouth, and nose, and otherwise alter the features; hence alterations in these characters in the face may be called its postures. The movements of the eyes being due to antagonistic muscles, the various ocular positions may be similarly termed.