24 Tra)is. A ((id. of St. Lauis 



Sphcx [Ammophila) uhhrcviata l-'ali. [ S. A. Ivoliwor]. 

 Two of tlu'si' woro socii in copulo at Wickes, Mo., on Sep- 

 tombor 4, 1917. Tlicy aliirlitod on a leaf nearby, reniainod 

 for porliaps tlirec minutes and resumed tbeir fliijlit liii^li 

 in tlie air witiiout separatin<j^. Anotlier ])air was seen 

 likewise, tlie male atop liis mate, on Auiifust l.'I. Tliey 

 liitted about with ease and rested frequently on the vege- 

 tation. On July 17, a female was seen carryini? a green 

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

 It was not dead. 



Sphex {Ammophila) procrra. These were seen at 

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

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

 and abandoned her first two attempts after making a 

 good beginning, ller 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 drop])ing it. 



Sphex {Ammophila )arqe}itatus Ilort. [S. A. Hohwer], 

 When first I saw this wasj) at work, I thought it was 

 Sphcx pictipennis , on account of the similarity of its 

 coloring and .size, but upon seeing it at work, 1 at once 

 saw that its method of proceeding was slightly dilTerent 

 from the fixed habits of S. pictipennis. The <lilTerence 

 in the behavior of the two species lies chiefly in the 

 method of carrving 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 iiiclu's distant. The 

 two individuals of S. at\qentata obsci'vcd at work on a 

 sandy area in St. Louis on September 1, 111 IS, wouM al- 

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

 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 tlial the sand was only a 

 thin layer which had been dumped on toj) of tlir hard 



