66 ^A- ECONOMIC ENTOMOLOGY. 



with eyes, leave the parent-nest in great numbers and fly about, 

 enjoying for a few brief hours the sun and air. They are then 

 said to be "swarming," and select their mates, returning to the 

 surface before the setting of the sun. Out of the vast numbers 

 leaving the nest few survive the day of flight. They have numer- 

 ous enemies, and, even if they escape these, must depend upon 

 being found and adopted by some vagrant workers before they 

 are able to form a colony. The sexed individuals — king and 

 queen — are helpless, can do nothing for themselves, and are not 

 permitted to return to their old home. This serves to keep the 

 insects in check, for the chances of starting a new colony are 

 very small. Let us assume, however, that a pair is adopted and 

 housed, the w^orkers at once building a proper habitation for the 

 royal pair. Reproduction begins immediately, and the female, 

 now stripped of wings by her own act, gradually enlarges, the 

 abdomen ultimately becoming a mere egg-sac. Such a queen 

 becomes the mother of the colony, and she is tolerably prolific : 

 sixty eggs a minute have been counted, making a possible output 

 of over eighty thousand in a single day ! The workers take entire 

 charge of the eggs and resulting young, feeding and tending 

 them until they are able to take part in the ordinary work of the 

 colony. Both males and females are represented among the 

 larval forms, but it seems to depend entirely upon the nurses as 

 to what caste is to result. They are able at will to arrest devel- 

 opment and to produce whatever forms are needed in the com- 

 munity. Thus workers and soldiers are each of both sexes, but 

 the sexual organs never become developed or functional. A 

 certain proportion are allowed to develop fully, and these furnish 

 the annual swarms. If the queen becomes old or unable to sup- 

 ply the colony with a sufficient number of young, the workers 

 provide for a number of " complemental" males and females. 

 These never become winged, reaching only the pupal stage in 

 which the wing-pads appear, and they never leave the nest, but 

 pair within it, the female laying fertile eggs, though never in such 

 numbers as a perfect queen. Therefore, several of these comple- 

 mental pairs may inhabit a colony, and there may be no real 

 queen at all. Curiously enough, no queen of our common species 

 has ever been found, and we are yet in ignorance of just where 

 the royal chamber is situated. 



