40 LESSON VIII. 



you had picked up, without entering into a long 

 description of each, what would you do ? 



Child. I would tell him their names. 



Teacher. But if he had never seen the shells 

 before, what idea would the name convey to 

 him ? If I told you that I had a murex in my 

 hand, what notion would you form of this shell ? 



Child. None at all, unless you shewed it to 

 me. 



Teacher. But if you had seen the shell, 

 observed its peculiar form and appearance, and 

 been told that it was called a murex, what would 

 then be the effect of my telling you that I had 

 another murex in my hand ? 



Child. I should know exactly what kind of 

 shell you meant. 



Teacher. This will give you some idea of 

 the advantages of scientific classification. In the 

 various branches of natural history, those ob- 

 jects which resemble each other in essential 

 characters are formed into a class or genus, a des- 

 cription of their points of resemblance is drawn 

 up, and a name affixed to the class. When 

 we have become acquainted with these charac- 

 teristics, the name will recall to our minds the 

 idea of the set of things signified by it. 



Child. A name then becomes very useful. 



Teacher. How does it become so useful ! 



Child. By recalling to the mind the things 

 which it signifies. 



Teacher. What is the class of objects which 

 you are about to study ? 



