338 Bees as Plant Fertilizers. 
or male element, are on one plant or flower (Fig. 145): 
and the pistils that grow the ovules—the ale elemen 
on another. Here, then, insects must act as ‘(mar ee 
priests” that fructification may be accomplished at os n. 
other plants where the organs are all in the same aie. 
fertilization is wholly dependent on insects. The pollen 
crains 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 fig wort (Fig.144), 
Fic. 144. 
Blossoms of Figwort, after Gray. 
A Developed stamens and pollen, S In two left-hand flowers ripe stigma, 
Ss qa He hehane flower unripe stigma. P Unripe stamens, 
a 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 
color and odor in flowers are solely to attract 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 covered as 236:5, There is then 
‘entire reciprocity between the bees and flowers. The bees 
are as necessary to the plants as are the plants to the bees, 
