COLORS OF NORTH AMERICAN FLOWERS 



mustard, saxifrage, currant, rose, geranium, oxalis, spurge, 

 holly, balsam, vine, mallow, St.-John's-wort, roek-rose, cactus, 

 evening-primrose, ginseng, cornel families, and with three ex- 

 ceptions in the Umbelliferce. But in three genera of the butter- 

 cup family, the columbines, larkspurs, and monk's-hoods, the 

 violet family, and the pea family (Papilionacece) they are com- 

 mon. All these flowers are highly specialized, irregular, and 

 pollinated by bees. 



In the more primitive families of the Gamopetalce, the series 

 with the petals united into a corolla-tube, as the heath, prim- 

 rose, olive, honeysuckle, and madder families, blue flowers are 

 again absent. They belong chiefly to the gentian, phlox, water- 

 leaf, borage, verbena, mint, and figwort families; while a 

 second maximum is reached in the bellflower family {Cam- 

 panulacece) and the Composites. All of these families are of 

 comparatively recent origin, and they contain nearly 400 blue 

 and blue-purple flowers. In the mint and figwort families, 

 flowers of these colors are very numerous, and are often dotted, 

 striped, or maculated with white, yellow, and red. They pre- 

 sent the culmination of color display among flowering plants. 

 They are mostly bee-flowers, and the majority of bee-flowers 

 everywhere are red or blue. Of 100 species of bee-flowers in 

 the Alps, 34 are white or yellow, and 66 red or blue. In the 

 German and Swiss flora, 152 bee-flowers are white and yellow, 

 and 330 red, violet, or blue. Genera adapted to bees often 

 display a variety of colors, as violet, blue, brown, red, yellow, 

 and white, especially when they bloom in the same locality at 

 the same time, this contrast in hue enabling the bees to remain 

 more easily constant to one species. Common examples are 

 the aconites, sages, and clovers. 



These highly specialized flowers often possess intricate floral 

 mechanisms and very peculiar forms, as the skullcap, monkey- 



233 



