30 LESSON V. 



classify and arrange them. There is still one 

 point with respect to shells which we have not 

 considered ; I mean the situations which they 

 occupy. Where are shells found? 



Child. Most of them in the sea, but some on 

 land, and others in ponds and rivers. 



Teacher. Those which live on land, are 

 called terrestrial, from the Latin, terra, earth. 

 These mollusks feed on vegetables, and have al- 

 ways four tentacula, and their eyes are placed 

 at the tips of these organs. The shells which 

 are found in fresh water, are called fluviatile, 

 from the Latin fluviws, a river; they are gene- 

 rally of a corneous colour, and are semitrans- 

 parent ; their mollusks have only two tentacu- 

 la, which are flat, having eyes at the base. 

 The shells inhabiting the sea are termed marine, 

 from the Latin, mar e, the sea ; they are much 

 the most numerous, the most beautiful, and the 

 most highly prized. I will now recapitulate to 

 you the substance of the lesson of to-day, and 

 you must write it on your slates.* 



Shells resemble the hard coverings of insects; 

 the principal difference between them is, that 

 the former are only attached to the animal in 

 one or two places, while the hard case of insects 



* It would be desirable before the recapitulation, that the 

 teacher should question the pupils upon the points that have 

 been discussed, as in a preceding lesson. 



