1. XVII.l CLASSIFICATION '03 



touch. Some vegetables, however, seem to have a kind ot sen 

 sibility like that derived from the organs of touch m anivm Is ; 

 they tremble and shrink back upon coming in contact w ih 

 other substances ; some turn themselves round to the sun, as if 

 enjoying its ray*. There is a mystery in these circumstances 

 which we cannot penetrate ; and it is not yet fully known at 

 what point in the scale of existence animal life ends, and vege- 

 table life commences. 



CHAPTER XVII. 



General Principles of Classification Natural Families o/ 

 Plants. 



420. LET us now imagine the whole vegetable kingdom, 

 comprising innumerable millions of individual plants, to be 

 spread out before a botanist. Could he, in the course of the 

 longest life, number each blade of grass, each little moss, each 

 shrub, or even each tree ? If he could not even count them, 

 much less could he give each one a separate name and descrif)- 

 tion. But he does not need to name them separately, for fie 

 sees that nature has arranged therii into sorts or kinds. 



43JL. If you were sent into the fields to gather flowers of a 

 similar kind, you would need no book to direct you to put into 

 one parcel, all the red clover blossoms, and into another, the 

 while clover ; while the dandelions would form another group. 

 These all constitute different species. Nature would also teach 

 you that the red and white clover, although differing from each 

 other in some particulars, yet bear a strong resemblance. 



432. By placing species together you form a genus, and to 

 this genus you refer all the different kinds of clover. When 

 yoa se<i red, damask, and cinnamon roses, you perceive they 

 all have such strong marks of resemblance as to entitle them 

 to be placed together in one genus. 



433. But yet you know that the seed of a damask rose would 

 never produce a red rose. One species of plants can never 

 produce another species, however near may be their resem- 



'ance. 



434. The whole number of species of plants which have 



CI 



430. Is it necessary for the botanist to give a particular name tu 

 every plant! 



431. Do yoa heed a book to teach you to put flowers of the same 

 ori together! 



430. How is a genus formed 1 



433. Does one specie^ ever produce plants of another specie*'* 



43 1. What fiuiiber ot spools have been discovered! 



