CLASSIFICATION OF ANGIOSPERMS. 235 



IV. ORDER XYRIDALES OR FARINOS^E. 



The plants are mostly perennial herbs of tropical and sub- 

 tropical America. The order includes a number of families 

 among which is Bromeliace^, to which the pineapple (Ananas 

 sativus) belongs. Pineapple is a native of Brazil and is now cul- 

 tivated in warm countries of the eastern and western hemispheres. 

 The fruit contains a proteolytic enzyme resembling trypsin and 

 also a milk-curdling ferment. The bast fibers of the leaves are 

 used for textile purposes. Some of the Bromeliaceae are epi- 

 phytic (air-plants), the best known member being probably the 

 Florida moss {Tillandsia iisneoides) which is used in upholstery. 



The family Commelinaceae is represented in the United States 

 by Qgmmelina or day-flower, some species of which have medic- 

 inal properties. The roots of some tropical species contain 

 saponin, as C. deficiens, of Brazil. The rhizomes of a number 

 of species of Commelina contain notable quantities of starch and 

 are edible. The spiderworts (Tradescantia) common in rich 

 soil in the United States, and the Wandering Jew (Callisia 

 repeks) commonly cultivated as an ornamental plant, also belong 

 to this family. 



V. order liliales or liliiflor^. 



The plants of this order are mostly perennial herbs with rhi- 

 zomes, tubers, bulbs, or fibrous roots. The leaves are parallel- 

 veined except in the rushes ( Juncacese) where they are long, slen- 

 der and cylindrical (radial). 



a. LILIACE^ OR LILY FAMILY.— The plants are the 

 most typical of the Monocotyledons. They are scape-like herbs 

 with bulbs or corms; the flowers are symmetrical, and the peri- 

 anth is parted into six more or less distinct segments (Figs. 123; 

 124, A). The fruit is a loculicidal capsule. The following plants 

 yield official drugs: 



Veratrum viride is a plant two to eight feet high, which is 

 characterized by the broad, clasping, strongly veined leaves, and 

 by having the flowers in large terminal panicles (Fig. 129). The 

 plant is found in swamps and wet woods in the United States in 



