June, '19] VICKERY AND WILSON: WINGLESS MAY BEETLES 243 



They were working along the edge of this area and were migrating 

 outward and destroying the cotton as the}' went. The cotton was 

 planted in rows extending north and south and the beetles seemed to 

 prefer to follow the rows as the heaviest migration was northward. 

 Most of their fresh entrance burro w^s were found in a strip about five 

 yards wide around the bare area. This strip was also marked by 

 many newly damaged plants. 



Here we found the beetles in the soil in very large numbers, often 

 from 6 to 13 in one foot length of the cotton row. Beetles were found 

 in all parts of the field in small numbers and a few in the brush on the 

 north side of the field where they had probably migrated from the 

 infested part of the field. 



By the latter part of June the beetles had almost disappeared. It 

 was estimated that a total of about forty acres of cotton was destroyed, 

 aggregating a loss of about $2,000. 



Food Plants. — These beetles were observed in the field feeding on 

 cotton, beans, corn, and sorghum; and on Russian sunflower in the 

 laboratory garden. In the laboratory cages they were fed on Amaran- 

 thus and alfalfa. Both of these plants were eaten readily. They ate 

 of the corn leaves which were put into the cages but did not relish this 

 plant. Cotton was the favorite food plant in the field. These beetles 

 were sometimes seen nibbling on the leaves of young Panicum fascicu- 

 latum reticulatum Torr. However, this grass apparently did not suit 

 their taste as the plants were left in the rows where the cotton had been 

 completely destroyed. 



Experiments with Control Measures. — Large quantities of the 

 beetles were hand-picked at night and killed by means of kerosene by 

 the Gembler family. But on account of the extremely large numbers 

 this process was not only a tedious one but almost ineffective. 



On April 25 we prepared three pounds of bran mash and scattered 

 in this cotton field where the beetles were numerous. The mash was 

 made according to the following formula: 



Wheat bran 24 pounds 



London Purple 1 } pounds 



Syrup 2 quarts 



On the following evening several dead beetles were found in this spot 

 on top and in the soil and several others apparently too sick to move or 

 feed. In some instances the poison took effect after the beetles had 

 entered the soil. More dead ones were found the second day after 

 the poison was put out than the first day afterwards. 



Two more batches of poison bait were put out on April 27, prepared 

 according to the following formulae : 



