338 



Bees as Plant Fertilizers. 



or male element, are on one plant or flower (Fig. 145)1 

 and the pistils that grow the ovules— the female elenaent 

 — on another. Here, then, insects must act as "marriage 

 priests" that fructification may be accomplished at all. In 

 other plants where the organs are all in the same flower, 

 fertilization is wholly dependent on insects. The pollen 

 grains must reach the stigma. Often this is from the very 

 structure of the flower entirely dependent upon insects. 

 Often as in willow-herb (Fig. 184) and figwort (Fig. 144), 



Fig. 144. 



Blossoms of Fig-wort^ after Gray. 



A Developed stamens and pollen, 5 In two left-hand flowers ripe stigma. 

 5 In right-hand flower unripe stigma, i* Unripe stamens, 

 n Nectar, 



as my colleague and esteemed Dr. Beal was first to dis- 

 cover, the pollen and stigma are not ripe simultaneously, and 

 so pollen must be brought from one flower to the stigma 

 of another, and this must be done by insects — chiefly bees. 

 Nature thus makes close fertilization impossible. Indeed 

 c61or and odor in flowers are solely to attiact insects for 

 the good of the flowers. In cases like the red clover, where 

 fertilization is possible without aid, my colleague. Prof. 

 Beal, has shown that unless insects are present the yield of 

 seed is meager indeed. The seeds in the uncovered blos- 

 soms were to those in the covei-ed as 236:5. There is then 

 entire reciprocity between the bees and flowers. The bees 

 lire as necessary to the plants as are the plants to the bees. 



