OLFACTORY SENSE OF THE HONEY BEE 343 



SO accurate th^t one might know what percentage died from the 

 operation. To cut off some other appendage or even the lower 

 part of the head, as Forel (74, '85) did, is not a fair test, because 

 such operations seldom expose sense cells and never any nerve 

 equal in size to that of the antenna, unless one pulls off the wings. 

 When the wings are pulled off the large nerve is severed between 

 the masses of sense cells and thorax, and the sense cells are not 

 exposed to the air, as they are when antennae are removed. 

 Even if the antennae are cut through the scape, the large masses 

 of sense cells belonging to Johnston's organs (Child '94) are sev- 

 ered. When the lower part of the head or the tarsi are cut off, 

 as Forel did, no nerves are exposed to the air except ends of 

 small nerves. From the foregoing it is only reasonable to assume 

 that when the antennae of any insect are injured in the least 

 degree, the insect is no longer normal and if it fails to respond 

 to odors placed near it, this negative response may be due to 

 the shock of the injury. 



The following criticisms based on a consideration of the mor- 

 phology of the antennae may also be offered. In the honey bee 

 the pore plates (Schenk '03) can scarcely be considered as olfac- 

 tory organs, because the drone has almost eight times as many 

 as the queen, and responds to the odors presented in slightly 

 more than one-half the time. It is true that those of the queen 

 are considerably larger, but even on this basis the reaction times 

 are not comparable. The pegs may be entirely eliminated as 

 olfactory organs, because they are absent in the drone, but are 

 abundant in the worker and the queen. Drones, queens, and 

 workers have about the same number of Forel's flasks and pit 

 pegs. Schenk's view that the pegs receive odor stimuli in the 

 queens and workers, while Forel's flasks and the pit pegs func- 

 tion in this way in the drones is inconsistent, because if the latter 

 two structures function for such a purpose in the drones why 

 should they not also in the females? Since these two structures 

 are few in number and many times smaller than the pegs, we 

 can not compare them physiologically. Thus it is seen that 

 not one of these antennal organs of the honey bee offers a solu- 

 tion for the ratios obtained with the use of the various odors. 



