INTRODUCTORY SURVEY 13 



D. The Spermatophytes or Seed Plants. — The dominant and 

 familiar portion of the earth's vegetation today consists of these 

 plants, which are well adapted for life on land and often attain 



Fig. 5. — A Fungus. One of the gill fungi, Pleurotus, growing on a log. 



great size. Their distinctive feature is the production of a 

 complex, many-celled reproductive body, the seed, in which is 

 contained an embryo plant and a supply of stored food. 



Seed Plants are very numerous and exceedingly varied in form 

 and structure, ranging from small and delicate herbs to huge trees 

 over three hundred feet tall. They are the most conspicuous and 

 best known of all the divisions of the plant kingdom, and provide 

 the great bulk of the foods, timbers, fibers, and other vegetable 

 products which form the basis of our civiUzation. 



