160 



son of 1904, namely, that Paris green is a specific for the pest. The 

 urgent demand for a specific was evidenced hj the very extensive use 

 of this substance. A portion of the great attention that it received 

 publicly was due to the fact that early in the season a certain num- 

 ber of weevils may be killed by it. Applications made by spraying 

 are even less efl'ective than dusting with the dry Paris green. As 

 was pointed out in a bulletin (Farmers' Bulletin No. 211), which goes 

 fully into the whole matter of the use of Paris green, it was explained 

 that the number so destroyed in the spring really means nothing 

 whatever to the crop later in the season when the plants have put on 

 squares and the poison is no longer effective. 



TRAPPING AT LIGHT. 



There is still in many quarters in Texas and Louisiana the sup- 

 position that it is possible to attract the boll weevil to lights. A 

 number of machines have been constructed based upon this idea. 

 Whether or not the boll weevil can be attracted to lights was one 

 of the first matters that was investigated by entomologists. During 

 September, 1897, Mr. J. D. Mitchell, of Victoria, Tex., a natu- 

 ralist and cotton planter, set out trap lanterns in a cotton field in 

 Victoria for one night, and sent the insects captured to this Bureau 

 for examination. In all, 24,492 specimens were taken, representing, 

 approximately, 328 species. Divided according to habit, whether 

 injurious or beneficial, the result was: Injurious species, 13,113 speci- 

 mens; beneficial species, 8,262 specimens; of a negative character, 

 3,117. The interesting point in connection with this experiment was 

 the fact that not a single specimen of the boll weevil was found, 

 although the lights were placed in the midst of fields where the insects 

 were very abundant. Since that time other investigators have looked 

 into this matter more fully. Lights have been kept burning in cotton 

 fields night after night for several weeks. In no case has a single 

 specimen of the boll weevil been discovered, although thousands of 

 species of insects have been captured. 



The popular misapprehension about the possibilit}^ of capturing the 

 boll weevil at lights is due to the fact that somewhat similar insects 

 {Balaninus mctoriensis) and other acorn weevils differ from the boll 

 weevil in that lights exert a strong attraction for them. During occa- 

 sional seasons the acorn weevils are exceedingly common in Texas, 

 and great numbers of them fly to the electric lights. 



REASONS FOR ADVANTAGE OF CTJLTTJRAL METHODS. 



The difficulties in the way of controlling the boll weevil lie both in 

 its habits and manner of work and also in the peculiar industrial condi- 

 tions involved in the production of the staple in the Southern States. 



