CHAPTER II. 

 THE SKELETON. 



1. The Skeleton. By the skeleton of any animal we 

 usually mean those hard parts which remain behind 

 when the softer parts have decayed; as the shell of a 

 clam or crab, or the bones of a bird or beast. In our own 

 bodies, bones form the chief part of the skeleton; but other 

 things help. A very young infant has a skeleton, but this 

 skeleton is made for the most part of cartilage, or gristle, 

 and not of bone. As the child grows, more and more 

 bone takes the place of the cartilage; but even in old age 

 some cartilage remains. Moreover, a skeleton consists 

 not merely of all the bones of a body, but of all the 

 bones united together in their proper places. In our 

 bodies they are bound together by tough stringy connec- 

 tive tissue. The skeleton of the living body, as distin- 

 guished from a dead skeleton made of dry bones joined 

 together by wires, is therefore made up of three different 

 things; namely, bones, cartilages, and connective tissue. 



2. The Bones, two hundred and six in number (see 

 table, p. 22), form the hardest, and stiffest, and heaviest 



1. What is a skeleton ? What change takes place in the skeleton 

 of a child as it grows ? How are the bones of a skeleton put together ? 

 What are the materials of the living human skeleton ? 



2. Number of bones in the skeleton ? What part of it do they 

 make? How do they provide support? Protection? How con- 

 cerned in movement ? 



