INHABITANTS OF SHELLS. 



CHAPTER li. 



" CoNCHOLOftY," said Mr. Elliot, on resuming 

 the conversation with his children, '' is that 

 branch of natural history which comprehends the 

 study of testaceous animals, or animals with 

 shell-coverings^ and includes those of the seas, 

 the rivers, and the land. 



" All shells are formed of carbonate of lime. 

 This you may easily prove by applying a little 

 acid to a shell, and you will find that an effer- 

 vescence takes place. 



" The animals that inhabit shells are blood- 

 less, without bones, but provided with a heart, 

 lungs, and mouth, together with other organs 

 needful to their conformation. 



" Testaceous animals have the power of en- 

 larging their habitations ; they can also repair any 

 injury that may occur to them. 



" Many kinds of shell-fish are made use of by 

 man, and form a valuable article of food, such as 

 oysters, cockles, muscles, scallops. The whelk 

 is also used, and a species of murex. 



" A species of cowry is in use for money among 

 some people of Africa ; and pearls, so much 



