1901.] NATURAL SCIENCES OF rHILADELPHIA. 433 



one hundred days produce one pupa. But larvae grew from the 

 egg to nearly full size without insecl food, and one pupa, that later 

 on became a minim, had no insect food during the last twenty-two 

 days of its larval stage. The adult ants appear able to live on 

 indefinitely without insect food ; but there is a noticeable diminu- 

 tion in the number of eggs laid by the queen, and in the number 

 of the larvre simultaneously fed by the workers. I have seen no 

 instance of the eating of members of their own colony by these 

 ants, nor of their feeding their larvji) upon dismembered kin. But 

 they will eat and feed to their larvte the flesh of dismembered alien 

 callows, and probably thickness of integument is all that protects 

 alien adults from being commonly used as food. 



The responsibility taken by the workers in the care of the 

 young may have brought about an incapacity on the part of some 

 of the queens to regurgitate food, and may have disabled them for 

 solitary rearing of the larvre. 



Two sister queens that were taken at swarming on September 17, 

 lived each with a king of another colony until the death of both 

 kings, when I placed them, on November 13, together without 

 workers in a Petri cell where they lived until the following June. 

 The first egg was laid on December 8, and the first larva appeared 

 on December 28, when there were fifteen eggs, cared for by both 

 queens. The queens continued to lay eggs, and young larvte 

 frequently appeared among the eggs, but no larva lived longer 

 than two or three days. Up to April 28, four months after the 

 appearance of the first larva, no larva had been reared in this cell, 

 although more than one brood had meantime been successfully 

 reared in all similar cells where the queens were assisted by 

 workers. I then thoroughly cleaned the cell and replaced the 

 two queens. That same evening two eggs wei'e deposited, and 

 when, on May 7, the eggs had been increased to eleven, I put in 

 two full-grown alien larvie, and later on a white pupa, all of which 

 were accepted by the queens. On "May 24 the pupa became a 

 minor ant, and at once began to assist the queens in the care of 

 the eggs. On May 25 two new larv;c were to be seen among the 

 eggs, and these larvte continued to grow and live. The two intro- 

 duced larva? also thrived, and on June 10 the two queens and 

 three callows were together engaged in tending a promising group 

 of larvte, the first that were reared from eggs in this cell. 

 28 



