WASPS, SOCIAL AND SOLITARY 



walking from one to another of them instead of flying, 

 although the last part of the study was made on the 



wing. 



Cerceris deserta was one of the wasps that objected 

 strongly to our presence, and she also made a great deal 

 of fuss about leaving her nest. Nearly all the species 

 circle before leaving a spot to which they intend to 

 return, but deserta begins her flight with a series of 



SECOND LOCALITY STUDY OF A. UNICOLOR ! 



short zigzags in the form of a half circle on one side 

 of the nest. C. nigrescens, too, begins with semicircles, 

 while C. clypeata flies entirely around and around the 



1 The continuous line shows the course walked over by the wasp ; 

 the short marks at a right angle indicate resting-places ; the broken 

 line indicates flight. 



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