250 ENTOMOLOGICAL NEWS. [June, 'l2 



Series DIPLOPTERYGA 



Family EUMENIDAE 

 Odynerus annulatus Say. 



Leoti, Wichita County, Kansas, August 2ist, 1910. 



We were fortunate in finding two females of this species in 

 the act of searching for a suitable nesting place. This was 

 shortly before 9 A. M. The ground the wasps were survey- 

 ing was quite clear of vegetation in areas of several square 

 inches. Russian thistle was abundant everywhere, and at a 

 distance of about 100 yards north and east were small shallow 

 lakes or lagoons. At about 9.05 A. M., the first wasp having 

 chosen its building site, commenced excavating, and at 9.40 the 

 second did likewise. The locations chosen were about six feet 

 apart, and for convenient reference the first Odynerus (9.05 

 A. M.) shall be designated E (East) and the second W 

 (West) in accordance with the positions of their excavations. 

 They went to work as follows : 



The spot chosen was moistened, the earth thus softened was 

 removed and arranged around the slight excavation in the 

 form of a circular wall or tube. Odynerus worked but for a 

 minute or so when she flew away in the direction of one of 

 the lagoons, to return in an equally short time with her mouth 

 parts glistening with water. More moistened earth was taken 

 out and applied to the wall. In making the latter which is 

 rough exteriorly and smooth inside, Odynerus employs her 

 forelegs and mouth parts for the interior work and clings over 

 the side of the tube with her two other pairs of legs. The 

 abdomen is apparently applied to hold back the oncoming wall. 



After twenty minutes both wasps had excavated holes as 

 deep as, or deeper than, themselves and constructed a short al- 

 most vertical tube over them.* As the work advances only a 

 part of the pellets of earth extracted from the gallery are used 

 for tube construction, the rest are carried off and dropped sev- 

 eral feet away. It is noteworthy that Odynerus in disposing 

 of the pellets of earth (which she does when on the wing), 



*Later investigations show that the tube is often considerably bent. 



