LESSONS ON SHELLS. 



LESSON I. 



ON THE MOLLUSCA. 



Teacher. Do you know what these things 

 are which I have brought in as the subject of 

 our lesson to-day ? 



Child. They are shells. 



Teacher. Describe to me what you mean by 

 a shell. 



Child. Oh, a shell is that which covers a 

 snail. 



Teacher. Very true ; a snail has a shell, but 

 in saying this you do not explain to me the na- 

 ture of a shell. When you attempt to describe 

 anything, you should give such an account as 

 would instruct a person altogether ignorant on 

 the subject. Try again, and tell me what a 

 shell is. 



Child. A shell is a hard covering or house 

 belonging to animals resembling slugs. 

 B 



