268 A TEXTBOOK OF BOTANY [Ch. VI, 1 



Flowers are also clistinguishod b}' odors, which, liowcver, 

 do not occur in all, perhaps not in the majoritj^ at least so 

 far as our comparatively dull sense can perceive. When 

 present, they are usually pleasing, or fragrant, to us, though 

 a few, like Skunk Cabbage, are positively repulsive. Con- 

 trary to a popular belief, fragrant odors and bright colors do 

 not commonlj' go together, at least not in wiki plants ; for 

 in general the most fragrance occurs in flowers of which the 

 colors are not especially visible, while odors are unusual in 

 plants of exposed habit, — in meadows, roadsides, or prairies. 

 Thus odors supplement a certain defect of color in making 

 known the presence of flowers. 



In size, flowers range very widely. The t^'pical size in 

 those which occur separately would perhaps exceed somewhat 

 an inch across ; but thence they range down to almost mi- 

 croscopic dimensions, as in certain small floating water weeds, 

 and upward to the truly gigantic proportions of the tropical 

 Rafflesia, in which a single flower is more than three feet 

 across (Fig. 61). Everybody knows that some connection 

 exists between flowers and insects, and it is true in general, 

 as we shall presently see, that a relation exists lietween flower 

 size and insect size. Between flower size anrl conspicuous- 

 ness, there also exists a correlation in this way, that while 

 the larger flowers are commonly solitary, the Siualler occur 

 massed together into clusters, acquiring thus a collective 

 prominence, the perfection of which is found in the com- 

 posite heads of the Daisy, Sunflower, and others of their 

 family. 



In shape, flowers are strikingly multiform. Simplest are 

 those which have no showy parts at all, but only the incon- 

 spicuous sexual parts. Of the more familiar kinds, some 

 are regularly concave, like Buttercups and Apple blossoms, 

 with the sexual parts in the center, l.nit tluMice they range 

 to such elongated forms as the Fuchsia, and, becoming ir- 

 regular, produce bizarre effects in the (hciiids, even to a 

 degree simulative of insects or other unrelated natural ol> 



