Vol. XXlii] ENTOMOLOGICAL NEWS. 251 



does not cast them about indiscriminately for it was observed 

 that W dropped them at a distance of from four to six feet 

 east of its nest, while E disposed of hers to a distance of about 

 three feet in a direction W. N. W. from its burrow. 



A note made at 10.30 A. M. reads : "W took out three 

 pellets of moist earth in succession, dropped them and then 

 flew away east for water. The tube she was building was over 

 one-half an inch high and taller than that of E, notwithstand- 

 ing the fact that E had commenced building about half an hour 

 earlier than W." The pellets which are used for tube build- 

 ing are moistened yet more when brought up to the surface. 



As the tunnels neared completion the wasps appeared to 

 work less systematically and regularly and stayed away longer. 

 At 10.52 A. M., W seemed to have finished its tube. 



On August 22 and 23 the wasps were occasionally watched. 

 At that date, however, their tubes were finished and aside 

 from noting that they took occasional trips (we saw one of the 

 two make seven trips in thirty minutes, and bask in the sun), 

 nothing of interest was observed. However, some of the ac- 

 tions of Odynerns must have escaped our notice, for at 8.35 

 A. M. of the following day (August 24), each wasp was seen 

 to bring in a larva of the Pyralid Loxostege sticticalis, which 

 must have been nearly mature, but nevertheless was easily car- 

 ried in air by the hymenopteron. These larvae were exceed- 

 ingly common on Russian thistle. A few hundred yards away 

 from our camp we noted an army of these worms composed of 

 thousands of individuals, marching in a northerly direction. 



At 9.30 A. M. of the same day (August 24) we caught and 

 killed E and dug out her nest. The tube over the hole was 9-16 

 inch high, nearly y\ inch diameter inside measurement, and 

 had an uneven rim (see PI. XIV, fig. 6). The tunnel was verti- 

 cal for 1 *4 inches and from that depth curved in a westernly di- 

 rection for 1^4 inches. The terminal cell, which was slightly 

 greater in diameter than the gallery and horizontal, was not 

 yet closed, but contained two sticticalis larvae, paralyzed so as 

 to be almost incapable of motion. Evidently Od\ncrns had but 

 begun provisioning its nest. It did not, however, delay laying 



