THE HOMING OF THE MUD-DAUBER. 22 5 



almost every experiment of this series the lower shade of window 

 number one was raised half way and the top curtain all of the way. 

 This was done in order to have the departing wasp confronted, on 

 each trip, by an upper and a lower bright patch. Were the wasp 

 responding to a bright patch merely and not to a bright patch in a 

 definite place, then the wasp should have flown to the upper bright 

 patch just about as often as it did to the lower. The wasp always 

 flew directly from the nest to the opening in window number 

 one ! There was but one exception to this statement. On one 

 occasion I was standing on a ladder watching the wasp construct 

 the nest. I was within two feet of the nest. On that occasion 

 the wasp, on departing, circled about once or twice and then 

 returned to the nest and from there flew to the exit. 



In brief, these experiments warrant the conclusion that the 

 flying mud-dauber, like the creeping ant, is guided by certain 

 landmarks, and that light plays a prominent role in furnishing 

 such landmarks. 



Haines Normal School, 



Augusta, Ga., July 25, 1908. 



