54 



These figures become even more striking in consideration of the 

 fact that the cotton leaves were often purposely left until they became 

 moldy and decayed or dried and wholly unfit for food. It was at 

 such times that most of the weevils sought the sweet in preference. 

 Should we leave out of the account the weevils found at the molasses 

 or sirup when the cotton was unfit for food, the number attracted 

 there would be reduced fully one-half. In either case the fact remains 

 that none of the sweets can be said to have attracted weevils from 

 the cotton leaves. 



INFLUENCE OF SWEETENED WATER UPON FEEDING OF WEEVILS ON 



COTTON PLANTS. 



It is easy to demonstrate that weevils will in confinement feed 

 upon sweet solutions. To prove that they will show the same attrac- 

 tion to it in the field is a far more difficult matter. 



For the purpose of these experiments, cheap molasses was used, 

 mixing 1 part of molasses with 25 jiarts of water, as is generally 

 recommended in spraying formulae. Three pairs of young plants 

 which had not begun to square were then selected from those growing 

 upon the laboratory grounds. The plants in each pair were of equal 

 size, and both in healthy condition and standing closely enough 

 together to be both covered bj^ one cage. One plant of each pair was 

 then dipped in the sweetened water, while the other was left in its 

 natural condition. In each of the cages 10 weevils were then placed 

 upon the ground and midway between the bases of the plants. The 

 object of the test was to see which plant, the treated or untreated, 

 would attract the larger number of weevils. During the first three 

 days observations were made several times each day. Weevils found 

 upon either plant were counted at each observation. 



A summary of the observations made on the first day before the 

 liquid had dried showed 15 weevils upon the sweetened plants and 16 

 on those not sweetened. These results were so remarkably even that 

 no attraction or repulsion could be ascribed to the liquid before it 

 dried. 



During the ten days covered by the observations, however, 63 wee- 

 vils were found upon the unsweetened plants and only 45 upon those 

 sweetened. The weevils fed largely upon the petioles and somewhat 

 upon the blades of the leaves and the main stems of the plants. No 

 indication was observed of special feeding upon the "gloss" left by 

 the drying of the sweetened water. In each cage the normal untreated 

 plant was destroyed before the treated one. During the first half of 

 the observations 52 weevils were found feeding upon the unsweetened 

 plants and only 32 upon the sweetened. Only after every leaf on the 

 untreated plants hung black and dead, while the sweetened plants 

 were in much better condition, did more weevils attack the sweetened 

 plants. 



