CHAPTER V* 



PLANTS AND ANIMALS DISTINGUISHED 



IT may seem an easy matter to draw a line between 

 plants and animals. Who cannot tell a cow from a 

 cabbage ? Who would confound a coral with a mush- 

 room ? Yet it is impossible to assign any absolute, dis- 

 tinctive character which will divide the one form of life 

 from the other. The difficulty of defining an animal 

 increases with our knowledge of its nature. Linnaeus 

 denned it in three words ;f a century later, Owen declared 

 that a definition of plants which would exclude all 

 animals, or of animals which would not let in a single 

 plant, was impossible. Each different character used 

 in drawing the boundary will bisect the debatable ground 

 in a different latitude of the organic world. Between 

 the higher animals and higher plants the difference is 

 apparent ; but when we reflect how many characters the 

 two have in common, and especially when we descend 

 to the lower and minuter forms, we discover that the 

 two " kingdoms " touch, and even dissolve into, each 

 other. This border land has been as hotly contested 

 among naturalists as many a disputed frontier between 

 adjacent nations. Its inhabitants have been taken and 

 retaken several times by botanists and zoologists ; for 

 they have characters that lead on the one side to 

 plants, and on the other to animals. To solve the 

 difficulty, some eminent naturalists, as Haeckel and 



* See Appendix. 



t " Minerals grow ; plants grow and live ; animals grow, live, and 

 feel." 



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