BEES AS BUILDERS OF FLOWERS 



and directly in front of this cone stands the stigma, on the lower 

 side of which there is a flexible, lip-like projection. To reach 

 the nectar a bee must run its tongue through the centre of the 



Fig. 20. Blue Violet. Viola cnmiUata 



A bee-flower; the veins on the lower petal serve as nectar-guides; the spur, or nectary, is 

 shown in the two lower flowers 



cone of anthers; and when it is withdrawn the grains of pollen 

 cling to its moistened surface, while the lip of the stigma bends 

 it away so that self-pollination is prevented. But when the 

 proboscis is inserted in another flower a portion of the pollen 



49 



