18 THE EICE WATER-WEEVIL. 



USE OF TRAP LIGHTS FOR ADULTS. 



The appearance of adults at artificial lights at night has suggested 

 the plan of placing lights in the fields and trapping the weevils which 

 may be attracted. Great numbers of the weevils seek the electric lights 

 of stores in the towns throughout regions where the insects abound. 

 Ordinary lights in dwellings are sometimes frequented. At Crowley, 

 La., more than a hundred weevils have been collected within a few 

 minutes on a single store window. They appear most numerously 

 on warm dark nights, but, like many other insects, they do not fly to 

 lights in any considerable number when the moon shines. Neither 

 does the time of their flight seem to last long, for as soon as dark- 

 ness has settled, most of them come in a rush, and only occasionally 

 do stragglers show themselves later in the night. Their seasonal 

 appearance begins from the 1st to the middle of April, and about the 

 middle of August thej^ become very scarce. 



Tests of the efficiency of light as a practical means of attraction 

 were conducted at Crowley. A portable acetylene outfit was used to 

 furnish light, being operated near rice fields 1 mile from town. Some 

 of the best results were as follows, the weevils being taken on a 

 cloth screen that was provided for the purpose of inducing them to 

 alight : 



On the night of May 26, 1910, Mr. Van Dine started the light at 

 8 o'clock and captured over 40 weevils in the first 15 minutes. Later 

 the breeze increased and only strong flying insects came to the light. 



Starting the light at 8 o'clock on July 19, after a day of heavy 

 rains. Mr. Hood collected 24 weevils in 45 minutes. But on the night 

 of July 29, which Avas clear and warm with slight south breeze, he 

 placed the light in the middle of a rice field and caught 125 weevils 

 between 8 and 9 o'clock. 



SUGGESTIONS FOR PROTECTIVE TREATMENT. 

 POISONING ADULTS. 



"When the weevils gather in particular portions of a rice field, as 

 they often do along deeply flooded edges, dead furrows, and in spots, 

 opportunities seem to be presented whereby the application of a food 

 poison could be made effective. As the Aveevils indulge in rather ex- 

 tensive feeding compared with their size, the poisoning* of the 

 plants would be apt to cause the death of great numbers of the adults 

 that might feed upon the poisoned leaves. The application of the 

 poison should be made upon the first appearance of the insects before 

 they have had much chance to oviposit. The poison must be selected 

 with reference to its safety on the plants, and if in the form of a 

 powder, it could be easily distributed by means of a dust gun, from 



