248 ZOOLOGY. 



30. Lucernariu. Body gelatinous, wrinkled, and provided 



•with arms. 



31. Asterias. Sea-Star. Bodij contained in a flat, and 



mostly radiated coriaceous case or shell; which is 

 covered with numerous retractile tentacula ov papillece. 



32. Echinus. Sea-Egg. Body covered with a crustaceous 



shell ; mostly beset with numerous moveable spines. 



ORDER III. 



Testacea.— M0ii?7SC.</, 



COVERED WITH A CALCAREOUS SHELL OB SHELLS. 



This Order, to which the attention of Naturalists is now 

 generally directed, forms a distinct branch of Natural Ilistorj', 

 «nder the name of Conchology, it is composed of Animals, 

 for the most part belonging to some of the genera in th« 

 preceeding order, but provided with hard external coasts or 

 shells ; from the great difficulty experienced in procuring 

 the inhabitants of the shells, they have by general consent 

 been classed from the various forms of their tenements. 



Many kinds are applied by Mankind to the purpose of 

 food, the shells of others are manufactured into various 

 useful or ornamental articles ; they feed principally on 

 molluscous animals, and small insects ; some on vegetable 

 substances, and others on putrid animal matter ; and they 

 are devoured by various kinds of fish, and the larger moUusca. 

 The order is subdivided into three distinct families j compri- 

 sing in the whole, thirty-six genera. 



