NO. 14 SENSE ORGANS ON MOUTH-PARTS OF BEE — McINDOO 5 1 



certain modified hairs situated either in the mouth itself or on the 

 organs immediately surrounding it." " But though the lower 

 animals undoubtedly possess the sense of taste, it does not, of course, 

 follow that substances taste to them as they do to us. I have found 

 by experiment that sugar and saccharine, which are so similar to us, 

 taste very differently to ants and bees." 



In conclusion under this heading, the results obtained by the pre- 

 ceding authors are less satisfactory in explaining that insects have 

 a true gustatory sense than the results obtained by the present author 

 in showing that insects do not have a true gustatory sense, because 

 the preceding authors have found no organs anatomically adapted for 

 receiving gustatory stimuli. Even if the antennze are amputated, the 

 olfactory organs are not eliminated, because olfactory pores are 

 widely distributed over the integument, and for this reason the 

 olfactory sense cannot be eliminated while testing for the sense of 

 taste. The present writer's opinion is that insects do not have a sense 

 of taste, because their highly developed olfactory organs are suffi- 

 ciently capable of receiving the odors, however weak, from any and 

 all substances. Whenever the odors are extremely weak, it is then 

 necessary for the insects to eat a little of the foods containing the 

 undesirable substances before being able to smell these substances. 

 For this reason the present writer has called this faculty an olfactory- 

 gustatory sense, although according to the definition of the sense 

 of taste in vertebrates the gustatory perception plays no part in the 

 responses. 



GENERAL DISCUSSION 



The present writer, and the few other authors who have fed insects 

 foods containing undesirable substances, have observed that the 

 insects sooner or later refuse such foods after eating more or less of 

 them. Judging from this behavior, the other authors have concluded 

 that insects can taste, regardless of knowing whether or not they 

 have sense organs, anatomically adapted for receiving gustatory 

 stimuli, and without considering the role played by the olfactory sense 

 in these responses. As Parker has already said for vertebrates, and 

 as we well know for ourselves, it is almost impossible to determine 

 whether we taste or smell certain substances when we eat them. To 

 us sometimes a food, before being eaten, emits only a faint odor or no 

 odor at all ; but when we eat it, we perceive a pronounced odor. In 

 such a case the odorous particles are not given off until the food is 

 taken into the mouth and mixed with saliva. The same principle is 

 certainly applicable when bees eat candies which contain undesirable 



