AN ANT ENEMY OF THE COTTON BOLL WEEVIL. 



47 



It was soon found that the ant- made holes could, from internal 

 conditions if not from external appearances, be distinguished posi- 

 tively from those made by the weevil, and it was also possible to 

 tell with considerable certainty whether the victim was in the larval or 

 the pupal stage, tho in only a few cases had the ants left any remains 

 of their pre}^. A careful examination of the interior of a square 

 from which a weevil has emerged shows invariably a small quantity 

 of fine debris removed by the weevil from the wall of the square in 

 cutting its way out. Besides this, there is a small amount of white 

 excrementitious material, the final product of the transformation, 

 which is voided by the weevil before it leaves its cell. 



Fig. 7.— An ant enemy of the cotton boll weevil: a, cotton square showing emergence hole of boll 

 weevil; b, c, cotton squares showing entrance holes of Solenopsis geminata var. xyloni. Slightly- 

 enlarged (original). 



In cases where the squares had been entered by ants and an imma- 

 ture stage destroyed, neither of these signs of adult weevil activity 

 could be found, but the stage of the weevil could in most cases be told 

 from the presence or absence of the larval exuviae, which are generally 

 untouched by the ants. 



In the lot of 75 squares kept dry it was found that the ants had 

 entered 64, destroying 44 stages which were probably larvae and 20 

 which were probably pupae. Eleven squares showed no ant holes. 

 Of these, 7 contained no weevil stage, 3 contained live, unharmed 

 larvae of a parasite of the weevil (Bracon mellitor Say) and the 



