White and Greenish 



of our weeds are naturalized foreigners, not natives. Once released 

 from the harder conditions of struggle at home (the seeds being 

 safely smuggled in among the ballast of freight ships, or hay used 

 in packing), they find life here easy, pleasant ; as if to make up 

 for lost time, they increase a thousandfold. If we look closely at 

 a daisy — and a lens is necessary for any but the most superncial 

 acquaintance — we shall see that, far from being a single flower, it 

 is literally a host in itself. Each of the so-called white ' ' petals " 

 is a female floret, whose open corolla has grown large, white, 

 and showy, to aid its sisters in advertising for insect visitors — a 

 prominence gained only by the loss of its stamens. The yellow 

 centre is composed of hundreds of minute tubular florets huddled 

 together in a green cup as closely as they can be packed. Inside 

 each of these tiny yellow tubes stand the stamens, literally putting 

 their heads together. As the pistil within the ring of stamens 

 develops and rises through their midst, two little hair brushes 

 on its tip sweep the pollen from their anthers as a rounded brush 

 would remove the soot from a lamp chimney. Now the pollen 

 is elevated to a point where any insect crawling over the floret 

 must remove it. The pollen gone, the pistil now spreads its two 

 arms, that were kept tightly closed together while any danger of 

 self-fertilization lasted. Their surfaces become sticky, that pollen 

 brought from another flower may adhere to them. Notice that the 



Eistils in the white ray florets have no hair brushes on their tips, 

 ecause, no stamens being there, there is no pollen to be swept 

 out. Because daisies are among the most conspicuous of flowers, 

 and have facilitated dining for their visitors by offering them count- 

 less cups of refreshment that may be drained with a minimum loss 

 of time, almost every insect on wings alights on them sooner or 

 later. In short, they run their business on the principle of a 

 cooperative department store. Immense quantities of the most 

 vigorous, because cross-fertilized, seed being set in every patch, 

 small wonder that our fields are white with daisies— a long and a 

 merry life to them ! 



Since all flowers must once have passed through a white stage before 

 attaining gay colors, so evolution teaches, it is not surprising that occa- 

 sional reversions to the white type should be found even among the 

 brightest-hued species. Again, some white flowers which are in a transi- 

 tion state show aspirations after color, often so marked in individuals as 

 to mislead one into believing them products of a far advanced colored 

 type. Also, pale colors blanch under a summer sun. These facts must 

 be borne in mind, and the blue, pink, and yellow blossoms should be inves- 

 tigated before the reader despairs of identifying a flower not found in the 

 yjhite group. 



271 



