COMMUNICATION AMONG INSECTS — McINDOO 545 



is perhaps considerably different from that of a colony which 

 has a queen. The absence of a queen odor as a constituent of the 

 hive odor probably explains why the workers in a queenless colony 

 are irritable and never work normally. All the bees — workers, queen, 

 and drones — in a colony carry the hive odor of that colony on their 

 bodies, among the hairs. This odor serves as a sign, or mark, by 

 which all the occupants of a hive know one another. Since the queen 

 and drones are " aristocrats," they seem to disregard the sign that 

 has been thrust upon them, but whenever a queen enters the wrong 

 hive she is soon made to realize that she wears the wrong badge. 



Worker bees returning to the hives from the field pass the guards 

 unmolested, because they carry the proper sign, although the hive 

 odor that they carry is fainter than when they left the hive, and 

 it is partially masked by the odors from the nectar and pojlen 

 brought by them. 



Bees kept in the open air for three days lose all the hive odor 

 carried on their bodies, but each bee still emits its individual odor. 

 When a colony is divided the hive odor in each half soon changes, 

 so that by the end of the third day the original colony possesses 

 a hive odor so different from that of the separated half of the cojlony 

 that when workers from the two new colonies are placed together 

 in observation cages they fight one another as though they had 

 been separated all their lives. 



Although a foreign hive odor calls forth the fighting spirit in 

 workers, the queen odor under certain conditions seems pleasant to 

 workers whether the queen belongs to their hive or to another hive. 

 Even though the queen odor forms a part of the hive odor, it is 

 probable that to the workers this odor stands out prominently 

 from the hive odor. The fact that workers do not miss their queen 

 for some time after she has Jeft the hive indicates that her odor 

 thoroughly pervades and qualifies the hive odor, and that whenever 

 this constituent odor grows faint the workers " know " that she is 

 not among them. 



There has been much speculation concerning the ruling spirit or 

 power in a colony of bees. The present writer is inclined to believe 

 that a normal hive odor serves such a purpose. The hive odor is a 

 means of preserving the social life of the bees from dangers without, 

 and the queen odor which is a part of it insures continuation of the 

 social life within. As already stated, the workers " know " their 

 hive mates by the hive odor they carry. This odor insures harmony 

 and a united defense when an enemy attacks the colony. The 

 queen odor constantly informs the workers that their queen is present. 

 Even though she does not rule, her presence means everything to the 

 bees in perpetuating the colony. Thus, obeying the stimuli of the 



