149 



fields seemed to be successful, the irrigation of the plants necessary 

 in that climate resulted in the eventual destruction of the colonies, 

 consequently no practical results followed the experiments. Some 

 notes regarding this matter will be found in bulletin of the Comision 

 de Parasitology Agricola, vol. 1, No. 7, p. 252, and in vol. 1, No. 9, 

 p. 404. 



Ants are frequently to be found in squares on the ground in the act 

 of destroying larvae or more often pupae. Occasionally they have been 

 found entering infested bolls which are yet hanging upon the plants 

 and destroying the pupae, which had become exposed by the premature 

 cracking open of their cells. In some cases they have been known to 

 destroy young adults which had emerged but not become fully hardened. 

 Several species of ants are concerned in this good work. The most 

 active is a small red ant, Solenopsis geminata Fab. (fig. 8). Another 

 species belonging to the genus Myrmica also does considerable good. 



In a number of cases various species of 

 native ants have been observed in the act 

 of carrying off the bodies of weevils which 

 had died in the field. This has led numer- 

 ous observers to suppose that the ants were 

 killing the weevils; such, however, does 

 not seem to be the case, except possibly 

 in very rare instances. The principal at- 

 tack of the native Texas ants is directed 

 against the immature stages of the weevil, 

 and by destroying these they undoubtedly 

 accomplish a great deal of good. 



GUATEMALAN ANT. 



Fig. 8.— Solenopsis geminata Fab., 

 ant enemy of boll weevil— much en- 

 larged (original). 



In April, 1904, there was discovered in 

 Guatemala a species of ant {JEctatomma 

 tuberculatum 01.) which seemed to exert a 

 controlling influence upon the multiplication of the weevil by killing 

 and carrying off the adults. This ant is called by the natives the 

 "kelep,"or cotton-protecting ant. Its habitat ranges between the 

 northern countries of South America and through Central America 

 as far north as central Mexico. The discovery that this species is an 

 enemy of the boll weevil was made by Mr. O. F. Cook, botanist in 

 charge of Investigations in Tropical Agriculture, Bureau of Plant 

 Industry. a 



Early in July Mr. Cook arrived in Texas with 89 colonies of these 

 ants, including about 4,000 individuals. These colonies were dis- 

 tributed among various typical localities in Texas, and observations 

 have since been carried on under the immediate direction of Mr. Cook. 

 An account of the introduction of these ants, and some general 



« U. S. Department of Agriculture, Eeport No. 78, May 27, 1904. 



