^sugwia 





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Diagram: of Flowees 



EXPLANATION 



Marvelous in diversity of form, yet linked by underlying 

 similarities, the many plants of the world have long been 

 classified in families, genera, and species, as well as in 

 larger groups. Family characteristics are present in all 

 the genera of a family. Generic characteristics are seen in 

 all the species of a genus, but each species has individual 

 characteristics that separate it from all others. 



The chief characteristics of many of the different fami- 

 lies are easily learned, e. g., the square stems, irregular 

 corollas, and nutlike fruit in the base of the calyx of 

 the mints, the compact heads of composites, the peculiar 

 flowers of euphorbias, etc. And when the student learns 

 to look for the essential characteristics of a plant new to 

 him, he has gained a knowledge that is the real key to 

 identification. 



The Parts of a Flower 



The different parts of the flower are in concentric circles 

 around the all-important seed-vessel in the center, which 

 has one or more pistils. 



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