CHAPTER XI. 

 SYSTEMATIC BOTAISTY. 



1. All individual plants which closely resemble each other 

 in every particular, or are so nearly alike that they may be 

 reasonably referred to an immediate common parentage, con- 

 stitute what botanists call a species. Thus all the Red Clover 

 plants are — unless subjected to some abnormal or peculiar in- 

 fluences — so nearly alike that a minute description, or an exact 

 figure of any one would be an accurate account or representa- 

 tion of any other individual; the same may be said of the in- 

 dividual White Oaks, Locusts, Dogwoods, May-apples, Dande- 

 lions, or any other kind of plants; each of these groups of 

 similar individuals, therefore, is a separate species. That 

 some species occasionally pass, by a series of intermediate 

 forms, into one another is well known. The large majority 

 of species now existing, however, are well marked ; and 

 though usually very closely related to some others, their cha- 

 racters appear constant. 



2. The seeds of any species of plants will, when sown, pro- 

 duce individuals quite, or approximately, like the adult. The 

 same is true for all succeeding generations so far as is known 

 by actual experiment or observation. It sometimes happens, 

 however, that certain individuals differ slightly, but evidently, 

 from the typical, i. e. the usual form. If the descendants of 

 these individuals differ in the same respect from the typical 

 form ; or, in other words, if their characters are constant, they 

 form a variety of that species. Thus the Cultivated Snow- 

 ball is a variety of the wild High Cranberry ( Viburnum opu- 

 lus). The latter has only the outer flowers of the cluster 

 enlarged and conspicuous (neutral) ; in the former they are 



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