ISELY: EUMENID^ OF KANSAS. 269 



making a zigzag flight before a small area in the face of the 

 cliff in which she located her nest. This zizgzag flight I had 

 supposed was a "locality study," to aid the wasp in finding the 

 exact spot again. This idea I owed to a suggestion fi-om the 

 Peckhams ; I considered it analogous to the many locality 

 studies they had observed. 



When I pinned two sunflower heads on the face of the clitf 

 in the midst of a colony, as I have previously described, and the 

 wasps absolutely ignored these decorations, my confidence in 

 their observational ability was shaken. The wasps flew di- 

 rectly to their tubes as if there had been no change in the ap- 

 pearance of the side of the colony. 



That afternoon I purposely knocked off two long tubes 

 when the owners of the nests were away. When the wasps 

 returned they flew without the slightest hesitation directly 

 into their uncovered burrows. I went to another colony and 

 paritally mutilated three other nests by knocking off the tubes 

 and cutting out a part of the burrow, and then with my knife 

 I made gashes in the bank for several inches around the en- 

 trances of these nests. Two of the wasps flew directly to their 

 burrows and entered as usual. The other wasp lit a few inches 

 at the side of the burrow, hesitated a moment, and then walked 

 directly into it. When observing these wasps they seldom 

 seemed to resent my presence. Usually they did not appear 

 to notice me at all. 



These wasps whose homes I had mutilated were not blindly 

 unaware of the change. At the time I broke the tubes the 

 wasps were enlarging their respective burrows. Apparently 

 the tubes were finished. But within ten minutes after I had 

 broken the tubes all of the wasps were building new ones. 

 Only one of them began work on the new tube at once ; all of 

 the others continued discarding their excavated pellets for 

 several minutes. All three of the wasps whose nests I had 

 mutilated with my knife inspected by depredations several 

 times before beginning the rebuilding of the tube. 



The effect of a strong wind upon the work of these wasps 

 I had opportunity to observe on the afternoon of July 4. A 

 gale was blowing furiously from the southwest, striking 

 diagonally the face of the cliff in which the Odyncnis colonies 

 were located. The temperature was high, as usual, and ordi- 

 narily I would have expected to see the colonies very active. 



