A STUDY OF THE SKELETON 



173 



cl 



of this fact, young children should not be urged to walk at 

 too early an age, lest they become bow-legged. 



Differences in the Skull. In the top of a very young 

 child's head is a space between the frontal and parietal bones, 

 called the fon-ta-nelle'. This opening 

 gradually lessens in size by the growth 

 of the surrounding bones until at the 

 end of the first or second year it is 

 completely closed. 



Differences in the Spinal Column. 

 We have already noted the union that 

 takes place in the five bones of the 

 sacrum and in the four bones of the 

 coccyx. These consolidations are usu- 

 ally completed during the period from 

 the eighteenth to the thirtieth year of 

 life. 



Differences in the Breastbone. In dis- 

 cussing the breastbone, we compared 

 with its shape that of a dagger. This 

 bone also in childhood is formed of 

 several distinct parts. The four pieces 

 that make up the blade of the dagger 

 are usually united by the twenty-fifth 

 year, but a succession of ridges remain 

 which show the lines of union (see 

 Fig. 72). The handle and the point 

 of the dagger often remain as distinct 

 pieces until old age. 



Differences in the Bones of Ann and of 

 Leg. At the proximal end of the ulna 

 is a projection of bone (commonly known as the "funny 

 bone") which is readily felt at the elbow. Throughout 

 early life this bone is separate from the ulna and hence 

 it corresponds to the position of the kneecap in the leg. 

 It becomes united with the ulna at about the sixteenth 



FIG. 72. Sternum 

 viewed from Front. 



cl = places of attach- 

 ment of collar 

 bones (clavicles). 

 x = lower projecting 



end. 



1-7 = places of attach- 

 ment of first 

 seven ribs. 



