The Forms of Flowers. 87 



anthers? Sometimes the filament continues on above the 

 anther, as in violets. Have you any reason to give for the 

 peculiar behavior of stamens shown in Fig. 65 ? 



Get flowers of as many different shapes as possible for 

 the next work. 



EXERCISE 47. 



The Forms of Flowers. The shape of a flower de- 

 pends chiefly upon the forms of its parts, and their adhesion 

 or cohesion. Since the corolla is usually the largest of the 

 four sets of organs, its form mostly determines that of the 

 flower; but sometimes, as in fuchsia and zauschneria, the 

 calyx has more to do in shaping the flower than the corolla* 

 (See Fig. 59). It is, as it were, the chief color-bearer, for 

 it is as highly colored, and its parts, being united, are more 

 highly developed than those of the corolla. In lilies the 

 sepals play an equal part with petals in signaling insects, 

 and in shaping the display of color. Clematis, having no 

 corolla, shows white or purple stars made of sepals only. 

 When a calyx thus helps or does alone the work of a corolla 

 it is said to \>z petaloid. 



Unequal petals, or petaloid sepals, form an irregular 

 flower. Such flowers are usually one-sided and bilaterally 

 symmetrical ; but when the parts are of even numbers, as in 

 dicentra (commonly know as bleeding-heart), the flower may 

 not be one-sided. The shape as well as the position of a 



* Rarely stamens or pistils are the conspicuous organs of a flower. Then they 

 are often petaloid as to color at least. The calistemons or bottle-brushes of Aus- 

 tralia are such flowers. In canna, which should be examined if possible, sepals, 

 petals, stamens and pistil are all petaloid and nearly exactly alike. 



