ORCHARD, GARDEN, AND FIELD INSECTS 147 



insects in a breeding cage. Estimate the damage done to some crops 

 by the flea-beetle. What is the best method of prevention ? 



Do you know the large moth that is the mother of the tobacco 

 worm ? You may often see her visiting the blossoms of the Jimson 

 weed. Some tobacco growers cultivate a few of these weeds in a 



FIG. 141. PROPERLY CARED FOR 



tobacco field. In the blossom they place a little cobalt or " fly-stone " 

 and sirup. When the tobacco-worm moth visits this flower and sips 

 the poisoned nectar, she will of course lay no more troublesome 

 tobacco-worm eggs. 



