THE FLOWER AND THE BEE 



The depth at which the nectar is concealed is another most 

 important factor in controlling the visits of bees. In some 

 flowers it is fully exposed on a flat surface where it is accessible 

 to all insects; in others it is at the bottom of a slender tube, 

 where it can be reached only by the larger moths. The familiar 

 fable of the crane and the fox is constantly illustrated among 

 flowers. As a matter of fact, bumblebees and butterflies avoid 

 rotate, flat flowers containing little nectar, since their long 

 tongues do not permit them to suck easily on such a surface. 

 On the other hand, it would be useless to look for the smaller 

 bees with short tongues on the larkspurs and clovers, for the 

 nectar is quite beyond their reach. 



As we take leave of the oligotropic bees it may be inquired 

 if there are any other insects, which visit only one species of 

 flower. There are many others, especially among butterflies 

 and moths. The flag-beetle (Mononychus vulpeculus) passes 

 its entire life on the blue flag (Iris versicolor). This small 

 weevil feeds both on the pollen and nectar, and sometimes 

 gnaws the floral leaves badly. The eggs are laid in the young 

 seed-capsules, where the larvae feed on the ripening seeds. 

 Both the adult beetles and the larva? are supported at the ex- 

 pense of the blue flag. The legitimate pollinators are bees, 

 and while the flag-beetle may rarely effect pollination, it does 

 far more harm than good. This symbiotic relation is a benefit 

 to the insect, but an injury to the plant. 



The night-blooming yucca, or Spanish bayonet, which flour- 

 ishes throughout the Southern States, is pollinated exclusively 

 by a small nocturnal moth. The larvae of the moth live in the 

 seed-capsule. Thus both plant and moth are reciprocally 

 dependent on each other, and the destruction of the one would 

 be followed by the disappearance of the other. But in most 

 instances the insect receives the greater benefit. 



