SOME SOCIAL WASPS 267 



the flight. The nest was anxiously watched all that evening, 

 but not until the next morning between 9 130 and 10 : 30 

 did they return. 



Nest no. 10 gave us three workers : one was without the 

 right antenna, one lacked the entire left antenna, and the 

 third lacked the right antenna and in addition bore the 

 white mark which proved that it had done the flight only 

 that morning. The next morning at 7 : 45 the first of the 

 above-named wasps returned, and between 1 1 and 11:20 

 the other two appeared. 



Nest 12 afforded us one worker with the left antenna 

 off. This one returned promptly, probably the same even- 

 ing, for at 6 : 30 p. m. she was still out, but at 6 o'clock 

 the next morning she was on the nest. This one made the 

 flight in the shortest time of all the competitors. 



This experiment shows very clearly that wasps in a nor- 

 mal condition and wasps minus one or the other of their 

 antennae, regardless of whether or not they have made the 

 same flight before in a normal condition, or whether their 

 first trip is made under handicap, find their way back to the 

 nest for this distance. 



It should be made clear that, in effecting the mutilations, 

 the antennae were cut as close to the base as it was possible 

 with a very fine dissecting-scissors. A tiny stump remained, 

 perhaps 3/1000 of an inch in length, from which a trans- 

 parent fluid oozed out. Critics might say that this stump 

 of an antenna may factor as a true sense organ. 



Experiment XII 



July 24. Wasps with various antennal mutilations were 

 taken to the mail-box and liberated, in the same way as in 

 Experiment Xlb. They were taken at 7 a. m. and set free 

 at 7 : 30 a. m. 



From nest 12 we took one wasp, tried for the first time, 



