26 LESSON III. 



LESSON III. 

 (Repetition of the preceding summary as usual.} 



Teacher. What organs in the mollusca have 

 we taken into consideration ? 



Child. The organs of sense and of motion. 



Teacher. And what other organs are essential 

 to animal existence ? 



Child. All animals must have organs by 

 which they feed themselves. 



Teacher. Have you ever observed snails 

 eating ? 



Child. Yes ; I have seen them devour a 

 leaf, and I should think they must have teeth. 



Teacher. They have two jaws which are 

 furnished with small teeth, fitted for cutting 

 vegetable substances. 



Child. Have all the mollusca mouths like 

 that of the snail ? 



Teacher. No, the mouths of each species, 

 as well as their other organs, are adapted to their 

 peculiar wants and habits. Some have only a 

 simple opening to receive the little animalcula 

 brought to them by the waves, and which do 

 not require mastication. Most of those which 

 live upon the produce of the vegetable kingdom 

 have a muzzle with jaws which are either horny 

 or armed with teeth. The carnivorous* mol- 

 lusca have usually a kind of proboscis ; this 



* From the Latin corne,J?esA, and toro, I eat. 



