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anther, to this is attached a thread-like affair known as the 

 filament. Bat in ths case of clover, however, the filaments 

 are united to form a tube; the anthers contain the pollen. 

 The pistil is also found in the keel. The lower portion is 

 the ovary, the narrow neck is known as the style, the tip is 

 the stigma The color of the clover flower is especially at- 

 tractive to insects. The honey which the insect seeks is con- 

 tained in the tube formed by the union of the fine thread-like 

 bodies, or filaments. 



When an insect like the bumble bee lights on the flower, 

 it uses the keel and wings (the latter being attached to the 

 tube containing the nectar) as a resting place, its weight 

 pressing the keel down and causing the pistil and stamens, 

 the latter being somewhat shorter than the pistil, to come in 

 contact with the under side of the bee's head. The insect is 

 certain to leave some of the pollen from another flower on 

 the stigma. The honey is obtained by the insect when it 

 thrusts its proboscis into the united filaments of the stamens, 

 the tube thus formed has a slit on the upper side to give 

 place for a free tenth stamen. Self-pollination, or pollination 

 of the flower from its own stamens, is not excluded, as the 

 insect leaves the fiowers. 



In order to reach the honey an insect must have a 

 tongue from .3543 to .3937 inches (9 to 10 millimeters) long. 

 The honey lies from .2755 to .3937 inches (7 to 9 millimeters) 

 deep. Any insect sufliciently heavy to press down the 

 keel can pollinate the flower. Bumble bees are, of course, 

 the common pollinators. Prof. Osborn informs me that he 

 has observed two common species (Bomhus pennsylvanicus 

 and B. fervidus). We have found Bombus americanus B. 

 yervidus, Apis mellifica. We also observed Alydus pluto. En- 

 chistus variolarans of Hemiptera. Of the Coleoptera the 



