BUZZING AND HUMMING. 1 49 



Every practised apiculturist knows that both workers 

 and drones emit a tone during flight, which is subject 

 to considerable variations, and that these often furnish 

 some indication of the particular "frame of mind" 

 of the insect at the moment. The reasons for some 

 of these differences have already been hinted, but it 

 would be extremely erroneous to conclude that the 

 wings alone, or even mainly, give out a note, in proof 

 of which an easy experiment may be cited. If one 

 of the larger Humbles — e.g., Bombus terrestris or 

 hortorum — be shut in a box, after removal of the 

 wings, or after they have been so gummed as to be 

 incapable of movement, a humming note will still be 

 produced, which, under the excitement of fear or anger, 

 may be even violent; anatomy showing that this sound, 

 which accompanies the true tone of flight, results from 

 a membranous vibration in the spiracles, the latter 

 being, amongst honey bees, especially developed in the 

 drone, whose sonorous qualities were referred to by 

 Shakespeare. Landois, to whom reference has pre- 

 viously been made, recognised three tones in the flight 

 sound : the first, produced by the wing beats ; the 

 second, sharper in character, by the vibrations of the 

 abdominal rings; the third, the most acute and intense, 

 from the action of the true vocal apparatus, placed in 

 the stigmatic orifices. He found that stopping these 

 orifices with wax brought the humming to an end at 

 once. The wings undoubtedly do the buzzing, but the 

 humming is as clearly the outcome of an apparatus 

 formed as follows : The spiracles (page 33) have each 

 lying behind them, in a vestibule (or sounding-box) 

 made by an enlargement of the commencement of 



