COLORS OF NORTH AMERICAN FLOWERS 



children of the sun." In the making of starch the leaf -factories 

 absorb most of the red, orange, and blue rays of light, but make 

 no use of the green, and hence the color of foliage is green, a 

 most fortunate result, since a landscape of any other hue would 

 have been almost intolerable. 



Most of the 223 insect-pollinated or self-pollinated green 

 flowers in northeastern America are small or even minute, as 

 in the pinweeds (Lechea). Many have no petals and their 

 color is due to the green calyx, as 15 species of the buck- 

 wheat family, 8 species of sandworts and chickweeds, several 

 species of the rose family, the rock-maple (Fig. 105), and the 

 water-purslane. Many green flowers show undoubted evidences 

 of retrogression, as numerous spurges, the water-milfoils where 

 the sepals and often the petals have been lost; while the 

 composite flowers of the wormwoods (Artemisia) and ragweeds 

 (Ambrosia) have retrograded until they have become wind- 

 pollinated. 



The flowers of the vine family depend chiefly upon their 

 fragrance to attract insects. The green petals never expand 

 but fall away by separating at the base and coiling spirally 

 upward. The fragrance which resembles that of mignonette 

 can be perceived at a long distance. Kerner relates that in a 

 journey up the Danube he found the whole valley of the Wachan 

 so filled with the scent of vine-flowers that it seemed impossible 

 that they could be far off, yet the nearest vines were 300 yards 

 from the boat. 



While, in general, green flowers are visited chiefly by flies, 

 beetles, and the smaller bees, as Clintonia borealis, the large 

 yellowish-green panicles of the false hellebore (Veratrum viride), 

 and the smaller clusters of the smilax family, there are a few 

 species which secrete nectar very abundantly and are visited 

 by great numbers of insects. Basswood is one of the most 



227 



