24 Trans. Acad, of St. Louis 



Sphex (Ammophila) ahhreviata Fab. [S. A. Eohwer]. 

 Two of these were seen in copulo at Wickes, Mo,, on Sep- 

 tember 4, 1917. They alighted on a leaf nearby, remained 

 for perhaps three minutes and resumed their flight high 

 in the air without separating. Another pair was seen 

 likewise, the male atop his mate, on August 13. They 

 flitted about with ease and rested frequently on the vege- 

 tation. On July 17, a female was seen carrying a green 

 caterpillar belonging to the Hesperiidae [S. B. Fracker]. 

 It was not dead. 



Sphex {Ammophila) procera. These were seen at 

 Wickes at the end of June, and on July 2, one was starting 

 to dig her well at Silica. She seemed hard to satisfy, 

 and abandoned her first two attempts after making a 

 good beginning. Her method of digging was to stand, 

 head downward, with her body straight up in the air, bite 

 out a chunk of earth and fly with it a short distance be- 

 fore dropping it. 



Sphex {Ammophila )argentatus Hort. [S. A. Eohwer]. 

 When first I saw this wasp at work, I thought it was 

 Sphex pictipennis, on account of the similarity of its 

 coloring and size, but upon seeing it at work, I at once 

 saw that its method of proceeding was slightly different 

 from the fixed habits of S. pictipennis. The difference 

 in the behavior of the two species lies chiefly in the 

 method of carrying out the soil when excavating the nest. 

 S. pictipennis always walks from the burrow and carries 

 the dirt to a pile at a point about four inches distant. The 

 two individuals of S. argentata observed at work on a 

 sandy area in St. Louis on September 1, 1918, would al- 

 ways, when leaving the burrow with a load of dirt, fly 

 into the air and drop the sand while they were on the 

 wing. 



At first it appeared, as just stated, that these two fe- 

 males were at work in a sandy area, but upon excavat- 

 ing the burrows I found that the sand was only a 

 thin layer which had been dumped on top of the hard 



