The Life of the Individual 107 



Since it may not at first glance be clear how the age at 

 which bees perform certain functions is determined, it may 

 be well to explain the simple method by which this is accom- 

 plished. If the queen is removed from a colony of black 

 (German) bees and a yellow (Italian) queen is at once in- 

 troduced, for a period of twenty-one days after the removal 

 of the old queen the young worker bees which emerge from 

 the cells are black, since they are the progeny of the old 

 queen. At the end of that time, however, the worker brood 

 from the black queen has all emerged and yellow bees begin 

 to appear. The time at which the yellow bees first perform 

 certain functions may now be determined. This experi- 

 ment may be variously modified, as by the removal of all 

 the brood of the black queen at once or by the placing of 

 a frame of brood from an Italian colony in a colony of black 

 bees. The introduction of Italian bees into Germany and 

 later into America has been an important factor in enabling 

 investigators to learn many of the phenomena of the hive, 

 for the use of bees of two colors 1 is often of the highest 

 importance. 



The labor within the hive. 



When the workers first emerge from the cells they take 

 no part in the work of the hive for a day or two, nor do they 

 leave the hive. The first flight in front of the hive is usually 

 when they are about a week old, if the weather is favorable, 

 and these flights are continued on warm bright days until 

 they are nearly three weeks old. Although they do not go 

 far at first they may remain on the wing for a considerable 

 period. That these early flights are necessary in enabling 

 the young bees to void their feces is indicated by the fact 

 that if confined they become restless. 2 The abdomens of 

 young bees are frequently distended with feces. 



1 Another method of marking bees for observation is mentioned by Cas- 

 teel, Cir. No. 161, Bureau of Entomology, p. 5. The method employed 

 was to paint bees with different colors and also to number them. 



2 This was observed when colonies containing young bees were placed 



