THE SKELETON 



61 



102. The Vertebral Column. The 



spinal column consists in the adult of 

 twenty-six bones (Fig. 53). Twenty- 

 four of these bones have a similar 

 shape, and each is called a vertebra 

 (Latin, "that which turns "). The 

 other two have the names of sacrum 

 and coccyx. The first seven verte- 

 brae are in the neck and are called 

 cervical ("of the neck "). The next 

 twelve are those to which the ribs 

 are attached and are called thoracic 

 or dorsal ("of the back") (see Fig. 

 49). The next five vertebras are in 

 the loins or lumbar region and are 

 called lumbar (" of the loins "). They 

 are the largest of the vertebrae. The 

 lowest lumbar vertebra rests upon 

 the sacrum ("sacred," because this 

 bone of lower animals was once used 

 in sacrifice). In infancy the sacrum 

 consists of five vertebrae ; these begin 

 uniting at two years of age and com- 

 plete the union at twenty years. The 

 coccyx ("cuckoo," from resemblance 

 to bill of cuckoo), or last bone of the 

 column, is that part of the skeleton 

 which in the lower animals forms the 

 tail. In infancy it consists of four 

 small bones which later unite into one. 

 The coccyx is of little use, but the sa- 



tTr 



FIG. 53. Spinal Column 

 (seen from behind). 



crum is a highly important bone, since '^te^ST *" 



to its sides are attached the bones of 7 cervical, 12 thoracic, 5 ium- 



- . i bar, vertebrae. Do the sacrum 



the pelviC arch, by Which the Weight Of and coccyx show evidence of 



the body is transmitted to the legs. J n t | J"" divided in early 



