298 ANIMAL LIFE 



most important is the care of the young. In a new 

 colony begun by a solitary queen no workers are 

 present. This queen forms a small burrow, lays some 

 eggs, and when these hatch she feeds, cleans, and 

 tends the larvae and pupae. These emerge as workers 

 of different sizes, and they at once relieve the queen of 

 most duties. They extend the colony, make roads, 

 hew wood, draw water, and, above all, tend the young, 

 not only cleansing them of every speck and germ, 

 taking them upstairs for warmth and downstairs for 

 safety, but supplying with their own lips and con- 

 veying to those of the larvae all the nourishment 

 that the young require. The quality of this nourish- 

 ment is probably the decisive factor in the sex and 

 character of the offspring. By increasing the amount 

 of fatty saliva, comparable to the royal jelly of bee- 

 workers, which the nurse supplies, she can produce 

 a queen instead of a worker, and probably some slighter 

 difference in the quality or quantity of the food she 

 affords, decides the size and character of the worker. 

 Possibly the nurse determines certain features of the 

 short-lived male brood, for as in bee-drones so among 

 ants it is probable that the males arise from eggs 

 different in composition from those which produce 

 workers, soldiers, or queens. This passion for nursing 

 has led to very curious results, for the workers in 

 many colonies are, as it were, not satisfied to rear only 

 their own kind, but extend their brooding care to 

 the young of other insects, even to the detriment of 

 their proper charges. The influence of this fostering 



