CHAPTER VIII 

 SPERMATOPHYTES. 2. ANGIOSPERMS 



THE REAL FLOWERING PLANTS 



78. General character. The Angiosperms have several 

 superlative features. They are the most advanced, the most 

 recent, the most conspicuous, and the most useful of plants. 

 The vegetation that covers the earth is in the main angio- 

 sperm vegetation, and when to this is added the fact that the 

 Angiosperms are almost the only plants that men use, it 

 is not strange that they were once thought to be the only 

 plants worth studying. Perhaps the best reason for study- 

 ing the lower groups is that Angiosperms may be understood 

 better. Some more definite appreciation of the relative 

 abundance of Angiosperms may be obtained from the state- 

 ment that about 450 different kinds (species) of living 

 Gymnosperms are known, while about 130,000 different 

 kinds of Angiosperms have been recorded. 



In the preceding chapter ( 66) it was stated that An- 

 giosperms differ from Gymnosperms in having the seeds 

 inclosed. The inclosing structure is the carpel, which thus 

 forms a " seed-vessel " of extremely variable appearance. 

 Using the terms applied to these structures in the lower 

 groups, the statement would be that the megasporophyll 

 incloses the megasporangia (ovules) . It must not be thought 

 that the inclosure of the ovules is the only character that 

 distinguishes Angiosperms from Gymnosperms. It is so 

 obvious a feature that it suggested the name of the group, 

 but there are many other important differences. 



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