METHODS OF KEPKESSION. 79 



Two devices were prepared, each consisting of a small wooden box 

 nailed to the top of a rounded 2-inch stake about 2 feet in length. 

 Around the support (stake) of one box a roll of the fur was tightly 

 placed, arranged so that the hairs projected downward and so that the 

 ants would have to crawl ''against" them in going up the stake. 

 Fur was not placed upon the other device. The latter was stuck in 

 the ground and a suppl}^ of honey placed in the box. The ants 

 visited the honey at once and as fast as they removed it the supply 

 was renewed. This continued for several days, when this device was 

 removed and the one %\dth the fur was put in its place, also with honey 

 in the box. The interruption of the "trail" confused the ants for a 

 little, but within a minute's time they were going up the new device 

 and working their way persistently among the hairs of the fur. In 

 a short time they were able to get tlii'ough it, w^hen they continued to 

 the food supply at the top and removed it as before. The workers 

 were forced to make their way slowly through the fur, wrestling in 

 turn with the hairs in their way, but at most the fur did no more than 

 delay them a little ; it did not repel them in the least. 



A'arious experiments were made ^viih certain proprietary and coal- 

 tar disinfectants for protecting food supplies from the ants. Wood- 

 work rubbed or painted with these substances was not crossed b}^ the 

 workers during periods of from 2 to 48 hours after the applications, 

 but none of these substances was effective for more than two days, 

 on of citronella seemed more distasteful to the ants and they would 

 not cross woodwork treated with it as long as the odor remained. 

 Evaporation of this oil is, however, quite rapid. 



The use of zenoleum powder was found quite effective. Sprinkled 

 heavily on the floors of infested houses it Idlled many of the workers 

 with which it came in contact and answered fairly well for breaking 

 up trails and causmg the workers to seek food elsewhere. It was 

 also found of some service in keeping ants out of the nests of sitting 

 hens. 



Pine tar was not effective. In an attempt to feed honey to bees in 

 the open air the feeder was supported on a stick around which were 

 placed two separate bands of fresh pine tar. The feeder was placed 

 out in the afternoon and by 6 o'clock the next morning the ants had 

 crossed both bands of tar and the honey was black with them. To 

 stop them, two fresh bands of tar were applied. Within 30 minutes 

 the ants which were trying to get out of the feeder had forced their 

 way into the tar in sufficient numbers to form a bridge and over tliis 

 the ants were soon passmg freely to and fro, despite the strong odor 

 of the tar itself. 



The following experiment proved the mefficiency of tobacco dust: 

 In the middle of a large iron pan with flat bottom was placed a dish 

 of honey. This dish was surrounded by a layer of tobacco dust from 



