A COURSE ON ZOOLOGY. 



CHAPTER I. 

 The Organization of Man. 



MAN is an organized being, that is, he is made up of 

 distinct parts, each of which performs a definite func- 

 tion. 



By organization is understood a combination of parts 

 or organs, the word organ being derived from the Greek, 

 and meaning an instrument or tool. 



The most superficial examination shows us that the 

 organs are arranged in a symmetrical manner in the 

 different regions of the body, which are the head, the 

 trunk, and the limbs. The head and trunk together 

 form the axis of the body ; the limbs are lateral append- 



A more minute examination reveals to us the existence, 

 in each region, of a solid framework covered by the soft- 

 parts and the skin, and protecting, in the head and trunk, 

 organs of great importance that fill the interior cavities. 



The framework, which gives its general form to the 

 body, is called the skeleton. It is composed of a large 

 number of pieces differing in form and in the manner 

 of joining together, and each piece is called a bone. To 

 the bones are attached the muscles that serve to move 



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