SOME SOCIAL WASPS 259 



promptly to the nest, one at n o'clock, one at 11:25 and 

 one at 1 1 140. 



Here we find a striking condition in the ability of one 

 individual which, as a youthful worker, could not return 

 to her nest in the barn fifty feet away, but as a queen at 

 the age of seventeen days, performed her homing task nicely 

 over a distance of one-eighth mile. This experiment like- 

 wise shows that, while other workers in other experiments 

 were lost at the same distance, these two workers nine and 

 ten days old made the trip promptly. 



From nest n, one orphan worker was taken. The 

 queen of this nest had been lost in Experiment III, on June 

 21 ; soon after this the nest was transferred to the wall of 

 the laboratory. This one wasp never returned to the nest. 



K4 and K6 were two orphan nests carried from Kimms- 

 wick, two miles distant, and pinned to the laboratory wall. 

 Two workers, one from each nest, which subsequently 

 emerged, were properly marked and used upon this occa- 

 sion. Neither of them returned. 



Nest 6. The queen from this nest was lost on June 20 

 (Exp. II). One of the first orphans to emerge soon there- 

 after was marked, and soon took up the duties of worker- 

 queen. This one was now used in this experiment, to- 

 gether with four workers of uncertain age differently 

 marked. The five were released along with the others at 

 10 : 30 o'clock. 



At 10:55 the worker-queen had already returned, but 

 up to i o'clock the workers had not appeared. The next 

 examination of the nest at 3 : 30 o'clock found two work- 

 ers besides the queen on the nest. This constitutes addi- 

 tional evidence of experience being a factor in aiding the 

 return flight, since of the eight that returned in this experi- 

 ment, five were old workers and three were of unknown 

 age, while none of the young workers returned. 



