44 LESSON VII. 



Child. To learn the names of shells, and 

 how to class them. 



Teacher. What do you suppose first led 

 people to adopt a classification ? 



Child. The wish to arrange their shells. 



Teacher. Yes, this would be one inducement, 

 but there are many more important advantages 

 of classification. Suppose that you had found a 

 variety of shells on the sea-shore, and wished to 

 inform a friend of the specimens you had picked 

 up, without entering into a long description of 

 each, what would you do ? 



Child. 1 would tell him their names. 



Teacher. But if he had never seen the shells 

 before!, what idea would the name convey to 

 him 1 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 showed 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 a 

 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 

 description of their points of resemblance is 

 drawn up, and a name affixed to the class. 



