THE FLOWER AND THE BEE 



ing their pollen inside the keel, wither up; while the five inner 

 stamens act as a piston and push out the pollen during an 

 insect visit. The blue lupine (Lupinus subcarnosus) , the State 

 flower of Texas, w^hich carpets large areas of land w^ith its hand- 

 some blue flowers, is visited by a great company of honey- 

 bees for pollen. 



In some pollen-flowers there is a curious division of labor 

 among the stamens, as in Cassia and Heeria. A part of the 

 anthers, called nutritive anthers, are designed to furnish food 

 to the visitors and are a conspicuous bright yellow; while a 

 part reserved for pollination are an inconspicuous green or the 

 color of the petals. In the mud-plantain {Heteranthera reni- 

 formis) there are two short stamens with golden-yellow anthers, 

 and one long stamen with a pale-blue or greenish anther. While 

 the bees are working on the short nutritive anthers, pollen is 

 deposited on their bodies by the long reproductive anthers. 



Pollen-flowers display every shade of color, as white, yellow, 

 orange, red, scarlet, pink, purple, and blue. The differently 

 colored varieties of the Hepatica, which may be found bloom- 

 ing in May, amid the brown leaves fallen from the trees during 

 the season previous, are well described by Burroughs: 



"Sometimes she stands in white array, 

 Sometimes as pink as dawning day. 

 Or every shade of azure made, 



And oft with breath as sweet as May." 



This variety in coloration is good evidence that the pollen- 

 flowers were once nectariferous. There can be little doubt 

 that at some time in their past history they all yielded nectar, 

 and that subsequently this function was lost. The occurrence 

 of isolated genera of pollen- flowers, as the roses in the rose 

 family, the elderberries in the honeysuckle family, and the tick- 



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