THE AEGENTIXE ANT: DISTEIBUTIOX AND CONTEOL. 11 



cent of naphthalene, and several other repellents. While bands con- 

 taining bichlorid of mercury and nicotine sulphate were effective 

 for slightly longer periods than the sticky substance alone, their use 

 is hardly to be recommended. 



INDOOR BARRIERS. 



Perhaps the most effective and durable barrier which can be used 

 indoors is a bichlorid-of-mercury tape or band. Tape is soaked in a 

 saturated solution of bichlorid of mercury and then hung up to dry. 

 It is then placed around the legs of tables, safes, etc., and if it is kept 

 dry will last from six months to a year. Common lampwick one-half 

 an inch wide is ideal for this purpose. After it has been treated in a 

 saturated solution of bichlorid of mercury and dried, pieces are 

 wrapped around the leg of the piece of furniture to be isolated and 

 ends lapped over tightly and pinned. The tape can be readily re- 

 newed by another soaking in bichlorid of mercury and repinned in 

 place. 



Twenty-five per cent of bichlorid of mercury mixed in shellac may 

 be painted around the legs of furniture, and when dry it will be quite 

 r.s satisfactory as the tape. 



Extreme caution is advised in handling hwJdorid of mercury^ as 

 tJiere is always an element of danger in using this poison. In recent 

 years the sale of this drug to the layman has heen practiccdly dis- 

 continued. 



A simple and efficient, though perhaps unsightly, barrier may be 

 made by placing the legs of furniture in saucers and putting a gen- 

 erous supply of moth balls in each saucer. The moth balls will 

 slowly volatilize, and it is necessary to add more from time to time, 

 but the ants will not cross the barrier thus formed. 



Coal oil placed in saucers in which the legs of furniture rest will 

 repel the ant, but the odor of the oil is disagreeable to most persons. 



ANT POISONS. 



Many and varied experiments have proved that it is futile to try 

 to exterminate Argentine ants with a poison which kills rapidly. A 

 few workers may be killed, but the masses of ants will quickly recog- 

 nize the source of fatality and avoid the " doctored " food. The few 

 workers killed in this way will have no effect in reducing the numbers. 

 None of this poison will reach the queens in the "nest, and it has been 

 found that it is essential to kill off the queens in order to prevent 

 further multiplication of the x^est. 



Soon after the writer took up the work on the Argentine ant Mr. 

 L. J. Xickels ^ published an article on the control of the Argentine 

 ant in California, in which a rather successful poisoned sirup was 

 described. It was decided to give this poisoned sirup a thorough trial 



1 Nickels, L, J. Field Work in the Control of the Argentine Ant. Jour. Econ. Ent., 

 V. 4, no. 4, pp. 353-358. 1911. 



