254 WASP STUDIES AFIELD 



Experiment V 



June 25. The queen of nest 2 failed to return to her nest 

 in Experiment II on June 20. The pupae were able to con- 

 tinue their development without her, however, and on June 

 24 two workers emerged and one on June 25. 



Of course, if these wasps find their way home instinc- 

 tively or through the aid of a sixth sense, we have a right to 

 expect the young wasps to return as readily as the old ones ; 

 if, however, age and experience are factors in directing 

 them home, the fledglings would be unable to return to the 

 nest since they lack both. 



These three were placed in large test-tubes and, without 

 the handicap of darkness so they could have every advantage 

 of studying their landmarks, they were taken to the mail- 

 box one-eighth mile distant along a level road (same as 

 Experiment I) and liberated at 7:40 a. m. They left the 

 tubes rather awkwardly (the direct activity and impatience 

 for escape, so noticeable in the queens, was absent), and 

 settled on the vegetation below. 



Four days of careful watching at the nests showed the 

 continuous absence of these workers. They were all un- 

 able to find their way home, despite the short distance and 

 the free use of their sense of sight. 



Experiment VI 



July 7. No further experimental work was done on the 

 wasps between the last test on June 25 and the present one 

 on July 7. In the interval, several workers had emerged 

 from the various nests. This experiment is the same as 

 Experiment V, except that a larger number of wasps was 

 used, which ought to give more conclusive evidence as to 

 whether the homing process is one of learning or o-f in- 

 stinct, or of some unknown sense. Thus ten workers and 



