12 



CHAPTER II. 



LINNiEAN ARRANGEMENT OF SHELLS. ANIMALS WHICH 



INHABIT THEM. 



Xhe Animal Kingdom is divided by Linneeus into six classes: 



The 1st, MAMMALIA, are viviparous.^ These have a heart with 



> 2 auricles and 2 ventri- 



The 2d, A VES, are oviparous. J cles, warm red blood. 



The 3d, AMPHIBIA, with lungs. -\ These have a heart with 



V 1 auricle and 1 ventri- 



The 4th, PISCES, with external gills. J cle, cold red blood. 

 The 5th, INSECTA, with antennae. 1 ^}'^''' ^f""" ^'^^^''^ ^^^h 



' ' ' ' auricle and no ventri- 



•^ Thesi 

 I 1 au 

 I cle,« 



J bloo 



The 6th, VERMES, with tentacula. J ;,\;' J^'^ '''"*' '^"^"' °' 



The sixth class, VERMES, or Worms, contains five orders: 

 The ist order is Intestina, or Worms, visually so called. The 

 greatest number of these inhabit the bodies of other ani- 

 mals. 

 The 2d, Mollusca, are of a soft substance, not covered with a 

 shell, and generally ftirnished with tentacula or feelers 

 (which are wanting in the order Intestina). These are 

 mostly inhabitants of the sea ; their forms are exceed- 

 ingly various, and many of them very extraordinary. 

 The 3d, Testacea, are Mollusca covered with a shell. These 

 are very numerous ; some inhabit the sea ; others fresh 

 water ; and others again the land. 



