Part 2 

 PLANT BIOLOGY 



Chapter 8 



SURVEY OF THE PLANT KINGDOM 



A detailed study of the entire plant kingdom cannot be made in such 

 a short chapter because there are over 300,000 species (diflFerent kinds) 

 of more or less well-known plants. Only a few plants which are repre- 

 sentative of the various subdivisions of the plant kingdom will be con- 

 sidered. A more detailed consideration of the structures and functions 

 of certain representative plants will be found in other chapters. 



In order to study properly and scientifically the representative mem- 

 bers of the plant kingdom, a system of classification must be utilized 

 by means of which investigators in all parts of the world may study the 

 same species of plants and call them by the same scientific name. With- 

 out scientific names and classifications, a certain plant might have a 

 large number of different names given to it by students in various parts 

 of the world. In the selection of languages for use in classification and 

 scientific names, Greek and Latin are used because they are more uni- 

 versally understood and because they are not so susceptible to changes 

 in each local community. In other words, these languages are more or 

 less standardized and consequently are very desirable for purposes of 

 classification and naming. Complete, accurate, scientific descriptions 

 and classifications of plants also make it possible to identify and correctly 

 name unknown species of plants. If we did not have specific scientific 

 terms and classifications, each investigator would more or less have to 

 make his own classification and follow his own methods of naming and 

 then would be unable to know if he were studying a form previously 

 described or if he really had a new species. 



For these reasons, the entire plant kingdom is divided into several 

 main divisions or phyla (singular, phylum). All of the plants included 



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