OLFACTORY SENSE OF THE HONEY BEE 271 



seized one of these dead bees it had trouble in freeing itself be- 

 cause of the interlacing of their hairs. The mouthparts of the 

 worker never came in contact with the oil of peppermint. After 

 some time every scented bee was removed from the alighting 

 board. The time taken to remove them varied from 10 seconds 

 to 36 minutes, with an average of 10 minutes and 19 seconds for 

 all 24 scented bees. Because of the repellent odor the bees were 

 three times as long in removing the bees so treated as in the case 

 of the untreated bees. 



A small piece of cotton wet with oil of peppermint was held 

 ^ inch from the bees that thickly covered one of the combs in the 

 observation hive. The time which elapsed before the bees had 

 scattered, leaving a circular space with a diameter of 3 inches, was 

 recorded. This experiment was performed 20 times with inter- 

 vals of 20 minutes between each two tests. The time varied 

 from 10 to 20 seconds, with an average of 16 seconds. Similar 

 experiments were performed with chemically pure oils of thyme, 

 clove, wintergreen, and cedar. The results obtained are as 

 follows: Oil of thyme 10 to 25 seconds, average 16 seconds; oil 

 of clove 15 to 45 seconds, average 21 seconds; oil of wintergreen 

 15 to 30 seconds, average 22.5 seconds; oil of cedar 20 to 45 

 seconds, average 29.5 seconds. The general average for the 100 

 experiments with all five oils is 21 seconds. Judging from these 

 results, peppermint and thyme have an equally repellent odor 

 to bees. To bees, as well as to human beings, cedar oil has the 

 least repellent odor of all five of these oils. 



EXPERIMENTS ON NORMAL BEES IN OBSERVATION CASES 



To determine the relative sensitiveness of queens, drones, and 

 workers to various odors, under conditions which permitted of 

 their close observation, triangular cases were used. These were 

 made of three narrow wooden strips, two of which were 10 and 

 the third 6 inches long, each strip being ^ inch thick. Cheese- 

 cloth served as a bottom and glass as a top for the case. The 

 apices and bases of these cases rested on two supports above a 

 rigid table and the table legs rested on a concrete floor, near a 



