CHAPTER TWENTY-THREE 



SEED PLANTS: ANGIOSPERMS 



FIG. 177. Roadside clump of bamboo, Philippine Islands. The bamboo is a very 

 important tropical monocot. 



ANGIOSPERMS (Greek : angio, receptacle, and sperm, seed) 

 form the second division of seed plants. The seeds are in- 

 closed in a pistil which later ripens into a pod or fruit. The 

 Angiosperms make up by far the largest part of the present 

 vegetation of the earth. There are more than 130,000 species, 

 as contrasted with 500 species of Gymnosperms and about 

 4500 species belonging to the fern group. In many forms the 

 stamens and pistils are surrounded by brightly colored floral 

 leaves. As compared with other groups of seed plants, a 

 most striking diversity of vegetative and reproductive struc- 

 tures is shown within the group. This diversity of form en- 

 ables Angiosperms to live in all land and water habitats, from 

 the margin of the ocean to alpine summits, and from the tropics 

 to the polar deserts. 



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