ISELY: EUMENID^ OF KANSAS. 289 



made her conspicuous. The situation in Osborne county was 

 made still easier for study because the nests of 0. dorsalis were 

 located in a pasture overgrown with the poppy mallow. This 

 often made it possible for me to follow a wasp from the nest 

 to the field, and after having observed the capture of a cater- 

 pillar to run back to the nest before she had pushed the cater- 

 pillar in. 



When 0. donaUs would come upon a crumpled leaf contain- 

 ing the larva of the spotted skipper, she would commence tear- 

 ing energetically at the silken nest, first at one end, then at 

 the other. Although the wasp worked furiously and without 

 pausing, sometimes more than five minutes were required to 

 dislodge the caterpillar. Usually, however, in less than a 

 minute the caterpillar would be jerked violently from its 

 cover, seized by the neck, and stung two or three times under 

 the thorax. Once I saw a wasp seize a caterpillar by the tip 

 of the abdomen to jerk it out of its nest, and sting it under one 

 of the last abdominal segments. Then she quickly seized its 

 neck and gave it three thrusts under the thorax. A vigorous 

 maxalation invariably followed the stinging. The capture of 

 a caterpillar generally occasioned considerable excitement on 

 the part of the wasp. Sometimes she would lose her footing, 

 and both insects would roll from the leaf to the ground before 

 the victim could be subdued. 



After maxalation, without further delay the caterpillar is 

 carried to the nest. 0. dorsalis always carried the caterpillar 

 in the same manner as did all the others of the genus that I 

 have observed. The caterpillar, head foremost and ventral 

 side up, is grasped by the wasp's mandibles and one pair of 

 legs. The wasp always flew directly to the burrow. Her 

 flight was usually quite slow, for the caterpillar seemed to be 

 a heavy burden. On alighting the caterpillar was pushed ahead 

 of her into the burrow, and the wasp, seizing its last abdominal 

 segment, followed it in. O. doi'salis was always in a hurry. 



The number of caterpillars in a cell, with the exception of 

 three cells, varied from five to seven. In Graham county, 

 August 19, I opened a nest with two cells containing three and 

 two caterpillars, respectively. A week later, in Norton county, 

 I opened a two-celled nest, containing five and two in each cell, 

 respectively. The caterpillars were all about the same size. 

 They were stored in a more or less tangled mass. In many 



