1958] 
Wilson — Chemical Releaser 
47 
TABLE 1 
Location of Olfactory Alarm Releasers in 
Pogonomyrmex badius Worker 
Body part 
Percentage 
of 
positive 
responses 
Intensity 
of 
effect 
Delay in 
onset of 
effect 
(range in 
secs.) 
Duration 
of 
effect 
(range in 
secs.) 
Duration 
of 
effect 
(M±s.e.) 
entire head 
100% 
moderate 
to 
high 
3-13 
15-150 
50 .7 ±: 17.6 
entire body 
minus head 
30% 
very low 
4-8 
10-15 
13.3 ±1.4 
mandible plus 
mandibular 
gland 
100% 
moderate 
4-9 
10-40 
28.0 ±2.3 
mandible alone 
lateral half of 
head minus 
0 
mandible and 
mandibular 
gland 
0 
Table 1. The effect on resting groups of workers of volatile sub- 
stances artificially released from various body parts by crushing. 
Each selected part was separately crushed between two pieces of 
glass and then quickly exposed at a point four to five centimeters above 
groups of resting workers collected just outside the nest entrance. The 
results given in this table come from ten replications of the experiment. 
The lag in onset of behavior was measured to the nearest second, the 
duration of effect to the nearest five seconds. In the case of a negative 
response, the crushed material was held in position one minute before 
being withdrawn. In the course of dissection it was found expedient to 
leave the mandibular gland attached to the mandible in order to 
preserve the contents of the reservor intact. Further explanation in text. 
