32 PHYSIOLOGY OF THE HONEY-BEE. 



wings is different in eacli of the three kinds of inhabitants 

 of the hive, and easily recognizable to a practiced ear. The 

 hum of the drone is the most sonorous. But worker-bees, 

 when angry or frightened, or when they call each other, 

 emit different and sharper sounds. On the production of 

 these sounds, bee-keepers and entomologists are far from 

 being agreed. 



"Inside of every opening of the aerial tubes is a valvular 

 muscle, which helps to control the mechanism of respiration. 

 This can be opened or closed at will, by the bee, to prevent the 

 ingress, or egress, of air. It is by this means that the air is kept 

 in the large tracheous bags and decreases the specific gravity of 

 the insect. The mainTesonant organ of the bee is placed in front 

 of this stopping muscle, at the entrance of the trachea." 



" The humming is not produced solely by the vibrating of the 

 wings, as is generally admitted. Chabrier, Burmeister, Lan- 

 dois, have discovered in the humming, three different sounds: 

 the first, caused by the vibrating of the wings ; the second, 

 sharper, by the vibration of the rings of the abdomen ; the third; 

 the most intense and acute, produced by a true vocal mechanism, 

 placed at the orifices of the aerial tubes." — (Girard.) 



76. The bee-keeper who understands the language of 

 bees, can turn it to his advantage. Here are some ex- 

 amples : 



•' When something seems to irritate the bees, who are in front 

 of a hive, on the alighting-board, they emit a short sound, z-z-z-, 

 jumping at the same time towards the hive. This is a warning. 

 Then they fly and examhie the object of their fears, remaining 

 sustained by their wings, near the suspected object,' and emit- 

 ting at the same time, a distinct and prolonged sound. This is a 

 sign of great suspicion. If the object moves quickly, or other- 

 wise shows hostile intent, the song is changed into a piercing 

 cry for help, in a voice whistling with anger. They dash for- 

 ward violently and blindly, and try to sting. 



" When they are quiet and satisfied, their voice is the hum- 

 ming of a grave tune ; or, if they do not move their wings, an 

 allegro murmur. If they are suddenly caught or compressed, 

 the sound is one of distress. If a hive is jarred at a time when 

 all the bees are quiet, the mass speedily raise a hum, which 



