: 
METHODS OF REPRESSION. 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 supply of honey placed in the box. The ants 
visited the honey at once and as fast as they removed it the supply 
tv as renewed. This continued for several days, when this device was 
removed and the one with 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 through it, when 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. 
Various experiments were made with certain proprietary and coal- 
tar disinfectants for protecting food supplies from the ants. Wood- 
work rubbed or painted with these substances was not crossed by 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. 
Oil 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 killed many of the workers 
with which it came in contact and answered fairly well for breaking 
up trails and causing 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 this 
the ants were soon passing freely to and fro, despite the strong odor 
of the tar itself. 
The following experiment proved the inefficiency 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 
