OR, MANUAI, OF THE APIARY. 147 



the jaws are closed they form an imperfect cone. Thus these 

 organs are well formed to cut comb, knead wax, and perform 

 their various functions. As we should expect, the muscles of 

 the jaw are very large and powerful (Fig. 60). Wolff's glands 

 empty at the base of these, and are doubtless excited by their 

 action — a proof that their secretion is gastric in nature. The 

 worker's eyes (Fig. 4) are like those of the queen, while their 

 wings, like those of the drones (Fig. 46), attain the end of the 

 body. These organs (Fig. 2), as in all insects with rapid 

 flight, are slim and strong, and, by their more or less rapid 

 vibrations, give the variety of tone which characterizes their 

 hum. Thus we have the rapid movements and high pitch of 

 anger, and the slow motion and mellow note of content and joy. 

 Landois proved many years since, that aside from the 

 noise made by the wings, bees have a true voice. Thus he 

 showed that a bumble-bee without wings, or with wings glued 

 fast, would still hum. This voice is produced in the spiracles. 

 "Who has not noticed that a bumble-bee imprisoned closely in 

 a flower still hums ? I have also heard a carpenter-bee in a 

 tunnel hardly larger than its body, hum loudly. Landois 

 found this hum ceased when the spiracles were closed with 

 wax. He describes quite an intricate voice-box, with a com- 

 plex folded membrane, the tension of which is controlled 

 through the action of a mascle and tendon. Thus we see that 

 bees have a vocal organization not very unlike our own in the 

 method of its action. The piping of the queen is probably this 

 true voice. Landois also states that bees and other insects 

 also make noise by the movement of the abdominal segments, 

 the one on the other. From the enormous muscles in the 

 thorax (Fig. 25) we should expect rapid flight in bees. Marked 

 bees have been known to fly one-half mile, unload and return 

 in six minutes, and double that distance in eleven minutes. 

 In thirty minutes they went two and one-half miles, unloaded 

 and returned. Thus they fly slower when foraging at a dis- 

 tance. These experiments were tried by my students, and the 

 time was in the afternoon. I think they are reliable. Pos- 

 sibly, early in the day the rapidity would be greater. Some- 

 times swarms go so slowly that one can keep up with them. 

 At other times they fly so rapidly that one needs a good horse 



