CHAPTER V 



CLASSIFICATION OF ANGIOSPERMS YIELDING ECONOMIC 



PRODUCTS 



IN this chapter will be given in natural sequence a list of the 

 principal orders of plants that yield medicinal and other economical 

 products. While great stress will be laid upon the plants used in 

 medicine, yet considerable attention will also be given to the other 

 economic substances furnished by the angiosperms, as food- 

 products, fibers, coloring principles, woods, and timbers, as well 

 a$ to the plants commonly cultivated for ornamental purposes. 

 It will be found that the number of plants useful to man is a very 

 large one, being derived from all the important families, so that in 

 their consideration the student will gain a rather comprehensive 

 view of the entire group. 



A. CLASS MONOCOTYLEDONE^:. 



The Monocotyledons are mainly distinguished as follows : The 

 embryo has only one cotyledon ; the leaves are mostly scattered and 

 parallel-veined ; the fibrovascular bundles of the stem are of the 

 closed type, and the flowers are typically trimerous. 



I. ORDER PANDANALES. 



This order includes members which are aquatic or marsh plants, 

 with narrow, elongated leaves and very small, imperfect and 

 incomplete flowers in spikes or heads. 



The TYPHACE^: or Cat-tail family has the flowers borne in 

 densely crowded terminal spikes, the staminate flowers being at 

 the upper end of the spike, while the pistillate flowers which are 

 beneath are more persistent. 



The SPARGANIACE/E or Bur-reed family have the flowers borne 

 in densely globose heads, the staminate heads being rather small 

 and near the upper part of the stalk, while the pistillate heads are 

 larger and situated a short distance below the staminate ones 

 (Fig. 252). 



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