OLFACTORY SENSE OF THE HONEY BEE 341 



As the structure of these pores is suitable for receiving chem- 

 ical stimuli and since all the foregoing experiments with these 

 organs indicate an olfactory function for them, it may now be 

 assumed that these pores constitute the olfactory organs in the 

 honey bee, and perhaps in insects in general. 



Table 2 gives the results of all experiments with worker bees 

 in timing their responses to various odors. The "three odors" 

 used are those from oil of peppermint, oil of thyme, and oil of 

 wintergreen. The "six odors" used are those from oil of pepper- 

 mint, oil of thyme, oil of wintergreen, honey and comb, pollen, 

 and leaves and stems of pennyroyal. 



GENERAL SUMMARY AND DISCUSSION 



The behavior of bees in observation cases is very similar in 

 many respects to that in the hives. Bees have a very acute 

 sense of smell. This sense is most highly developed in the drones 

 and least developed in the queen while that of the worker is 

 scarcely inferior to that of the drone. Olfactory pores are found 

 on the bases of all four wings, widely scattered on the trochanter 

 and at the proximal ends of the femur and tibia of all six legs, 

 on the second and third tarsal joints of most legs and generally 

 distributed on the shaft and lancets of the sting. Each pore is 

 a chitinous structure connected with a bipolar sense cell, the 

 peripheral end of which comes into direct contact with the ex- 

 ternal air. Such sense cells are met with in all insects for Kiin- 

 chel and Gazagnaire ('81) assert that bipolar sense cells are com- 

 mon to all insects. 



Bees with their antennae mutilated in the slightest degree, 

 either by amputation or by covering the surface, are never abso- 

 lutely normal. The more joints of the antennae severed, the 

 more abnormal the bees are. The antennae probably play no 

 part in receiving odor stimuli. The maxillae, labial palpi, man- 

 dibles, and sting either receive odor stimuli to a limited degree 

 or the mutilation in the experiments on these parts caused a slight 

 difference in the reaction time. Judging from their behavior and 

 longevity, bees with the wings either pulled off or glued at the 

 base and with the pores on the legs covered are normal, except 



