366 BOTANY: PRINCIPLES AND PROBLEMS 



Liliales (Fig. 98). — These include the Hly, amarylhs, and iris 

 famihes, perennial herbs with well developed bulbs or rootstocks. 

 The species usually have a conspicuous perianth and provide 

 some of our most beautiful garden flowers. 



Orchidales (Fig. 240). — The orchids are notable for the extreme 

 irregularity and great beauty of their flowers, and their remark- 



FiG. 239.— One of the Campanuhilos. Fig. 240. — One of the Orchidales. 



Yellow chamomile (Anthemis tinctoria), Showy lady's slipper {Cypripedium 

 belonging to the family Compositae. hirsutum), belonging to the family 



Orchidaceae. 



able specializations for insect pollination. They are particularly 

 abundant and brilliant in the tropics, whence they have been 

 introduced into the greenhouses of cooler chmates as the most 

 highly prized of exotics. 



With the development of the composite and orchid families, 

 the plant kingdom has reached the climax of its evolution. 



QUESTIONS FOR THOUGHT AND DISCUSSION 



790. Why have plants which reproduce by seeds rather than those 

 which reproduce by spores become the most successful part of the world's 

 vegetation? 



