THE OLFACTORY SENSE OF COLEOPTERA. 



429 



in the light and the more they were handled, the more satisfactory 

 they were to experiment with. Owing to this kind of behavior, 

 this species and several others used responded more slowly to 

 odors a short time after being caught than they did a few days 

 after being kept in confinement. This fact will explain why some 

 unmutilated beetles just caught respond to odors more slowly 

 than they do two or three days later after having had their 

 antennae pulled off. The following are the responses of this 

 ground beetle to the odors from the six different substances and 

 the average reaction times in seconds. 



Oil of peppermint: 



5 moved away quickly. 



5 vibrated antennae. 



4 arose quickly. 



4 moved slightly. 



2 moved antennae and legs. 



I worked legs. 



I kicked quickly. 



I vibrated antennae and legs. 



I vibrated legs. 



I jumped slightly. 



Reaction time 2 to 10 seconds, average 3.6 seconds. 



Oil of thyme: 



6 moved away quickly. 



5 moved quickly. 



5 moved slightly. 



2 worked antennae. 



2 moved antennae and legs. 



I arose slowly. 



I vibrated antennae. 



I moved backward slowly. 



I worked legs. 



I did not respond. 



Reaction time 2 to 60 seconds, average 8.5 seconds. 



Oil of wintergreen: 



5 moved away quickly. 



5 moved slightly. 



4 moved away slowly. 



3 moved quickly. 



2 vibrated legs. 



I arose slowly. 



Reaction time 2 to 60 seconds, average 16.4 seconds 



I stroked antennae. 



I vibrated antennae and legs. 



I worked antennae. 



I worked legs. 



I did not respond. 



Leaves and stems of pennyroyal: 

 10 moved away quickly. 

 6 moved slightly. 

 3 vibrated antennae. 

 3 worked antennae. 



Reaction time 3 to 60 seconds, average 21.1 seconds. 



I moved away slowly. 

 I vibrated legs. 

 I did not respond. 



Leaves and stems of spearmint: 

 5 moved away slowly. 

 5 moved slightly. 

 3 moved antennae and legs. 

 2 moved away quickly. 



2 did not respond. 



I worked mouth parts. 



I vibrated legs. 



I vibrated antennae and legs. 



