538 



A TEXTBOOK OF BOTANY 



[On. XIII 



of which the great petioles make up the apparent stem (Fig. 

 28). The^ flowers are usually in huge clusters, large, 

 showy, and zygomorphic (i.e. irregular in a way to facilitate 

 the visits of insects, page 276, 293). Most prominent is the 

 Banana ( flfgxa stapi ( entum ) , T the chief food plant of the 



tropics, which has been 

 propagated for ages by 

 man from its vegetative 

 shoots, and, like the 

 Pineapple under similar 

 circumstances, has lost 

 its power to produce 

 good seeds. Another 

 Banana (Musa textilis) 

 yields the Manila Hemp 

 of commerce, obtained 

 from the sclerenchyma 

 fibers in its petioles. 

 Here belong also the 

 Traveler's Tree of the 

 tropics, with its great 

 fan-form head, and the 

 Bird of Paradise Flower, 

 grown in our green- 

 houses. Closely related 

 are the Canna or Indian 

 Shot of gardens, and 

 the Marantas, of which 

 one yields Arrowroot. An allied family (Zingiberacece), has 

 the aromatic rhizomes which yield Ginger. 



FIG. 383. Orchid flowers, showing their 

 specialization of form. (From Figurier.) 



ORDER 9. ORCHIDALES (MICROSPERMM) : THE ORCHIDS. 

 With these plants we associate justly the most elaborate and 

 beautiful of all flowers. They include some 7000 species, 

 chiefly perennial herbs of warm regions, especially tropical 

 epiphytes of distinctive habit (Fig. 126). The flowers are 



