4 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 68 



ODORS EMITTED BY INSECTS 



Our experiences with the higher animals prove that practically 

 all of them emit odors, w^hich in most cases probably play a secondary 

 role to that of sight, but it is shown in the following pages that the 

 odors emitted by the honey-bee are the chief means of recognition. 



A. Odors Emitted by the Honey-Bee 



It has always been more or less a matter of conjecture as to just 

 how the different individuals of a colony of bees recognize one 

 another. Considering the five special senses of sight, hearing, touch, 

 smell, and taste which we experience, we may safely eliminate taste, 

 because the writer has recently (1916a) shown that bees do not have 

 a true gustatory sense, for it is only one phase of the olfactory sense. 

 Since it is more or less dark inside the hive, sight certainly can not 

 play a very important part in recognition, and since it has never 

 been proved experimentally that bees can hear we can not consider 

 hearing as the chief factor, and despite the fact that the writer 

 (1916a) has demonstrated that the tactile sense is quite acute, the 

 sense of touch in all probability is not as important as is the sense 

 of smell. The following pages give the experimental results concern- 

 ing the power of recognition among bees, which were brought about 

 by means of the olfactory sense, and the role played by the other 

 senses is not considered. 



Relative to the odors emitted by the honey-bee, von Buttel-Reepen 

 (1900) says: 



I believe that the following odors are present in a colony of bees : 



1. The individual odor. It can be easily demonstrated that the queen odor 

 varies with different individuals, and on the same ground (germinal variation), 

 an individual odor should be assigned to the workers. 



2. All offspring of one mother (queen) have a common inherited family 

 odor in addition to the individual odors, belonging only to the progeny of 

 one queen. 



3. The brood and chyle odor. 



4. The drone odor. 



5. The wax odor. Since the wax is a glandular secretion, an exuded 

 product, it may be safely taken for granted that, considered apart from the 

 specific odor of wax, the individual odors of the wax-generators adhere to 

 the honey-comb. Accordingly the wax structures of different colonies have 

 different odors. 



6. The honey odor. That the honey of each colony (mixed with a secretion 

 of the salivary glands) has its specific odor is readily seen from the old 

 practice of bee-keepers to which Bethe also alludes. If a queen be daubed 

 with honey from a queenless colony, she will be accepted readily by that 

 colony when inserted. 



