SOME SOCIAL WASPS 283 



seemed to be in a state of torpor, and would move only 

 when prodded. They were divided and part placed in a 

 box of excelsior out-of-doors under the south porch, part 

 in the laboratory, and part back under the eaves in the attic 

 where the temperature was intermediate between the other 

 two places. But one by one all died ; it could not be ascer- 

 tained among these limited numbers that any one location 

 was more favorable to them than the others. The P. annu- 

 laris survived for less than two days, but the last of the 

 rubiginosus females did not die until December 20. 



One June morning, a P. rubiginosus alighted on a potato 

 plant in the garden and immediately pounced upon a large 

 larva of a striped potato beetle, mumbled it in her jaws and 

 seemed to try to turn it over. After about forty seconds, 

 she suddenly dashed away, perhaps alarmed at our intru- 

 sion. The larva was apparently uninjured, and remained on 

 the leaf. 



They also feed upon flower heads, and are known to cut 

 open the fruits of Opuntia and other cacti and feed upon 

 the juices. 11 



Polistes annnlaris Linn. [S. A. Rohwer]. 



When, on April 7, 1915, we found P. annularis out in 

 great numbers, we were both astonished and delighted at 

 the propitious opening of the wasp season. They were 

 queens that had wintered over, and were taking advantage 

 of the first warmth of spring. 



The site of this first appearance of the wasps was the 

 east face of the high, rocky bluff overhanging the Missis- 

 sippi River at Cliff Cave, near St. Louis. Along this bluff, 

 in the warm morning sunshine, were hundreds of queen 

 "Bull. U. S. Dept. Agr. No. 113: 36, 45- 



