46 CONSCIOUS NERVOUS OPERATIONS 



directly to the spinal column. It has a shallow pit at one 

 of the upper corners for the end of the humerus, or upper 

 arm bone, and a projection to which the other bone of the 

 arch, the clavicle, or collar bone, is secured. The clavicle 

 is a round, slender bone, attached by its two ends to the 

 scapula and the sternum. 



48. The Upper Limbs contain, each, thirty bones. They 

 are the humerus, or upper arm bone ; the radius and ulna, 

 side by side in the lower arm ; the eight small bones of 

 the carpus, or wrist ; the five cylindrical bones of the 

 metacarpus, or palm of the hand ; and the phalanges, or 

 finger bones, fourteen in number, two being in the thumb 

 and three in each other finger. 



49. The Pelvic Girdle (Fig. 27) is formed by one large 

 spreading bone on each side, called the os innominatum, or 

 hip bone. On the outer side is a deep socket for the head 

 of the femur. The hip bones are made to support great 

 weight and to resist severe shocks. They sustain the 

 whole pressure of the trunk and of burdens carried, and 

 also receive the force of the various movements of the 

 lower limbs, as in running, jumping, cycling, etc. 



50. The Lower Limbs are similar in structure to the 

 upper. The femur, or thigh bone, the largest bone in the 

 body, corresponds to the humerus ; the tibia and fibula, 

 to the radius and ulna. In the ankle are seven tarsal 

 bones, and in the arch of the foot five metatarsals, to which 

 are added the fourteen phalanges, or bones of the toes. 

 There is, besides, a bony disk, imbedded in the great liga- 

 ment over the knee, forming a protection to the knee- 

 joint, and called the patella, or kneepan. 



51. Observe the provisions in the human skeleton for 

 securing firmness and strength to the upright figure. It 

 has been found that the arch is the strongest form of 



